STONE IN ARIZONA An Economic Study prepared for ARIZONA DEVELOPMENT BOARD

by

Roland C. Townsend Consulting Geologist Phoenix, Arizona THE ARIZONA DEVELOPMENT BOARD

1521 West Jefferson Street Phoenix, Arizona

PIERRE BAFFERT BERNARD M. MERGEN Chairman Director Santa Cruz County

ARLO WOOLERY M. E. HAFLEY Cochise County Mohave County

W. D. JAMES Coconino ROYALL SMITH County Navajo County

EDWIN D. SMITH HAROLD A. PATTEN Gila County Pima County

J. GREEN PAUL LOUCKS Graham County Pinal County

C. C. RILEY LEONARD SEXTON Greenlee County Yavapai County

DAVID R. MURDOCK HENRY F. COLMAN Maricopa County Yuma County

HARVEY PLATT Apache County CONTENTS

Page Acknowledgments • 4 II Introduction --- 5 III General 6 A History 6 B Present uses 7 C Industry economic status ...... 7 D Exploration 7 E Production and values . 8 IV Resources • 9 A Sandstone 9 1. Geology and areal extent, Coconino sandstone 9 2. Structure • 10 3. Composition and physical character 10 4. Production 11 5. Shipping - 14 6. Costs 14 7. Specifications, products, trends in use 14 8. Problems 15 9. Moenkopi formation 16 10. DeChelly sandstone ------16 B Marble -• ------16 1. Geology and areal extent 16 2. Composition and physical character 20 3. Production, products, shipping, and costs 21 4. Specifications and trends 23 5. Problems ...... - 23 C Tuff ------...... 25 ...... 1. Terminology and general geology 25 2. Character of representative deposits 28 3. Production ... 29 4. Problems 29 D Granite .--- .-. 31 E Slate ....--- 32 F Limestone ------33 G Schist ...... _. 34 H Miscellaneous stone ------34 1. Rhyolite and porphyry 34 2. Basalt and scoria . .--- 35 3. Travertine, tufa, and onyx marble 36 4. Quartzite and quartz 37 5. Jasper ------38 6. Copper stained rock ------._...--• 38 7...-.. Magnesite 38 8. Serpentine ------.. 38 CONTENTS

Page V Available Stone — Land Status and Acquisition of Mining Rights ------38 VI Transportation and Freight Rates ...... 40 A Railroads ------. - 41 B Trucking ------41 VII Labor Market ------42 VIII Depletion Allowance, Taxes, and Insurance ...... 42 IX Potential ------43 X Glossary ------...... ------.....-... - ... - 46 XI Annotated Bibliography ------48 XII Agencies Concerned With Stone Industry ...... 50 Map—Showing quarry sites and major transportation routes

I. ACKNOWLEDGMENTS

In preparing this report, many quarry operators and stone producers were con- tacted. Not a single one refused aid or data; each has contributed information about his experience in the stone industry, making the report possible. Use of specific data is noted in the report. In addition, several state and federal agencies made avail-able both time and information. Mr. Louis Smith and others on the staff of the Arizona Department of Mineral Resources provided valuable data on quarry locations and production. Mr. H. Wesley Peirce of the Arizona Bureau of Mines gave many valuable suggestions. Mr. Frederick C. Ryan of the Arizona State Land Department provided helpful data. Mr. Dee E. Reese and Miss Wilma Richard of the Arizona State Employment Service gave helpful data on the labor market. Also, in-formation on transportation was given freely by Mr. Hans M. Kruesl, Watson Bros. Transportation Co., Inc., Mr. Donald B. Malcolm, The Atchison, Topeka & Santa Fe Ry. Co., and Mr. C. F. Head, Southern Pacific Company.

4 II INTRODUCTION

The natural beauty of rock formations in Arizona is famed the world around. No wonder, then, that with the tremendous population growth in the west, stone pro- ducers and users are looking to Arizona for sources to supply the ever-increasing mar- ket. All of the principle types of building stone, and many unique varieties are avail- able within this one state. The purpose of this report is to draw together known data on occurrences of stone, present production techniques and problems, types and varieties of available stone, markets, labor and land conditions, and the general potential of the stone in- dustry in Arizona. Thus, the report is primarily an economic study. Data on building stone, landscaping stone, and crushed rock used in building for its decorative purpose are included; aggregate, ballast, rip rap, etc. are not included. Compilation of com- plete data on as widespread and varied an industry as this would probably be im- practical at this time. Therefore, an annotated bibliography has been included; ref- erence numbers in the text indicate items in the bibliography. Reference is also made to the state and federal agencies that can provide additional data. It is hoped that this report is sufficiently detailed to show basic trends, economics, and potential to both the present producers and those considering participation in this industry. Data have been gathered from many sources. A map is included showing by symbol the general location of many active and inactive quarries, as well as unworked prospects known to have a good potential. Over the years some stone deposits have been worked intermittently by various persons; an absolute count and check of re- ported locations has been unfeasable for this report. In some places several quarries are located within an area that must be represented by only a single symbol. Under such circumstances, omissions or errors in location are both unintentional and un- avoidable.

5 III GENERAL

HISTORY comprehension, compounding building needs. Stone is doubtless the world's earliest and old- Third, new equipment became available, from est building material, prized through the ages for power machines in quarries to guillotine cutters its strength and durability, for its adaptability to in stone yards, to high speed, economical trucks both simple and sophisticated construction needs, on new highways. At the same time, cross-country and for its decorative qualities. Trends in use have freight rates climbed, hampering shipping to the been determined by accessibility and local needs, west from traditional stone sources in the east. transportation, changing construction and stone While these factors may diminish somewhat, their production methods, and by current fashions. Ari- continuing effect at a steady rate will tend to sta- zona stone has been used since the earliest settle- bilize the stone industry. ment of the state. Until 1946, commercial produc- Immediateley after the war, building needs tion was intermittent, with local projects and use were simple, and were met with available mate- being dominant. Quarries were opened for tempo- rials. As the construction gap began to close, new rary markets or individual jobs, then virtually building techniques, materials and styles made abandoned. stone popular. Aluminum and glass enjoyed novel After World War II, several new factors con- uses, and steel in concrete changed structural re- tributed simultaneously to the development of the quirements. By themselves they are efficient, but Arizona stone industry. First, a building boom they tend to give a hard, cold appearance. Natural necessarily followed the war. Second, population stone was found to give texture and warmth to in west coast areas and in Arizona increased beyond structures. So the age-old concept of stone used

Section of field stone in a wall of cast slabs with exposed aggregate.

6 primarily structurally, changed to use of stone as a 8. Monuments facing or curtain wall, and use in places where its 9. Fireplaces and fireboxes decorative qualities are paramount but durability, 10. Landscaping — ground cover, uncut and strength, and low maintenance are also desired. crushed In addition, use of uncut and of crushed stone 11. Landscaping — planters, edging 12. Fines — aggregate, swimming pool copings increased. New building methods now allow for low and plaster pitched roofs with crushed stone coatings, and highly decorative and efficient uses of terrazo have become INDUSTRY ECONOMIC STATUS popular. Style changes have introduced exposed Basically, growth of the stone industry is de- aggregate, again combining the structural factors pendent on the construction industry, and in turn, on with decorative qualities. Fashions in landscaping population growth. The full potential of the state's have sent prospectors to the hills for sources of resources, and the most fficient production are flagstone, rubble, and crushed rock for walks, realized when a stable m rket of a size able to driveways, and gardens. Fines from crushing warrant substantial capita investment is attained. operations are being used in cast products. Although new uses of stone, wider range of products, One of the most important style trends has been and vigorous sales promotion can in-crease demand, to design almost any uncut stone into large wall long-term stability requires a large population within areas. Even otherwise nondescript stones, that might the optimum marketing area. as individual pieces lack attractiveness, such as field Obviously, before the end of World War II, stone, talus, or slabby boulders, may be used with Arizona alone could not suppoit a large stone in- attractive results. The only requirement seems to be a dustry similar to those in the eastern United States. common color or texture, such that the whole effect Even west coast markets were nbt easily developed. is that of a large mass. This mass effect, combined Today, however, factors mentioned above appear to with modern materials such as aluminum and glass provide a basis for a strong stone industry. Here- gives an appearance of both dignity and stability tofore, producers might be said to have "felt their found only in older buildings made wholly of stone. way" in expanding their part of the production. Few new business buildings in the Phoenix area lack Today, market demands sometimes exceed supply, a mass effect stone wall. Another trend opening new and stone materials usually available in Arizona are design possibilities has been to different mortar even imported. Today, producers are looking to joints; some are recessed, others abnormally wide. mechanization and otherwise increasing production, Some stones are cast into poured walls, giving the and to assuming processing functions now being stone an appearance of floating. In all, keeping done elsewhere. abreast of design trends has become an important phase of the stone industry. EXPLORATION

After being prospected for, more than a cen- PRESENT USES tury, Arizona would seem to have no geologic se- Today the uses of Arizona stone are many and crets. Indeed, most of its surface has been trod by 15 varied, but they can be grouped as follows: explorers, prospectors, miners, and geologists. Also, 1. Buildings — structural and decorative inasmuch as nearly all rock formations can yield dimension and uncut some material to meet basic construction require- 2. Roofing -- granular, crushed rock, insulation ments, the need for exploration for stone quarries 3. Terrazo — granules, aggregate would seem small. However, the character of rock 4. Inside flooring — sheets of stone formations may vary greatly froth place to place,2 5. Retaining and yardwall — cut and uncut and quality and style specifications require in- 6. Patios and walks — flagstone and crushed rocks creasingly greater selectivity of quarry sites. In order 7. Furniture -- table tops, benches for a producer to compete for markets, he must consider such things as accessibility, transportation, labor supply, and housing conditions in the

7 choice of a quarry site. Moreover, the success of a Workability — topography quarry may depend on geologic changes or variations overburden in the stone not apparent except by close fractures examination; a marble quarry may run into a fault or cleavage and partings shear zone, or a good "dune set" of beds in sandstone weathering may be truncated by a younger set. Many abandoned trends at depth quarries are testimony to the need for careful cutability selection of sites. reserves 7 In a recent publication, L. W. Currier has given PRODUCTION AND VALUES detailed procedure for the broad, geologic exploration By far the bulk of Arizona's stone production for quarry sites, and also describes the industrial has been carried on since World War II. Gross factors in evaluation of deposits, with particular production figures have beer compiled from time to reference to traditional producing areas in the eastern time,23 26 but only since 1953 have they begun United States. He points out that the lower production to show consistent trends, as below : from the far western states is not a measure of availability of suitable deposits, but is due to factors STONE PRODUCTION IN ARIZONA of population, economic conditions, and industrial (From Area Reports, Mineral Industry Surveys, development. These factors, plus the facts that U. S. Bur. Mines) 8 western deposits are more complex in distribution, YEAR TONS VALUE and market demands are for new construction forms 1954 1,205,452 $1,914,315 and new colors and textures, make exploration 1955 1,600,939 2,328,566 requirements somewhat different in Arizona. 1956 1,623,000 2,475,000 It should also be noted that for stone production 1957 2,101,000 2,982,000 1958 1,528,000 2,731,000 in Arizona, the character of most rock formations at 1959 2,468,000 3,998,000 any significant depth is not known. That is, no quarries have been developed to depths far be-low the The above figures are reportedly from mine weathered zone, or into `fresh' rock that is not shipments, sales, or marketable production, includ- affected by surface considerations of topography, ing consumption by producers. The average price per chemical alteration, fracturing, etc. Some formations ton of approximately $1.60 indicates that the figures may be seen at depth in mines, drill hole cores, and probably represent mostly production of limestone large open pits, but generally these are not cut in rock for cement, and of :rushed rock for aggregate. Even types that might be considered for large-scale stone the lowest values (quarry prices of unprocessed rock) production. of stone used for granules and for dimension stone Below is a brief outline of important consid- are in the magnitude of $4 and $10 per ton erations in exploring and prospecting for stone respectively. Because of the newness of the stone deposits in Arizona: industry, and its wide range of size and distribution of Type of Stone — sandstone, schist, marble, etc. operations, accurate data on total production and geologic formation; distribution values are not available. Economic factors — markets land status* However, a compilation f estimates by pro- access ducers of dimension stone an flagstone, crushed stone transportation as used in this report, nd decorative rock used in labor supply construction and landscaping, indicates the following Physical characteristics 1 — color and texture strength; compressive, tensile, shear, hardness, general estimate: toughness YEAR TONS VALUE porosity and absorption (wholesale-processed) insulation, reflection 1959 75,000 $1,575,000

* See land status considerations page 38 A more detailed account of values may be seen from a consideration of average quarry and

8 processed prices for representative materials. For IV RESOURCES example, in the case of marble crushed for roofing materials, some rock is sold F.O.B. quarries; hav- SANDSTONE ing passed an 8-12 inch grizzly and been roughly screened of fines less than to 3/4 inches. Here, prices average about $4.00 per ton. After process- At the present time, production from the pop- ing, the wholesale market price varies from $13 to ular Coconino sandstone dominates the stone in- $20 per ton, depending on bulk or bagged, trans- dustry in Arizona. It probably accounts for 75 per portation allowed, etc. In the case of sandstone, cent of both tonnage produced and dollar volume quarry products consist mostly of large sheets in a of sales. Although flagstone and dimension stone variety of thicknesses as needed to supply the mar- are quarried from as far east as Holbrook, and as ket. Here, average value at the quarry is about $7. far west as Seligman, the town of Ashfork is 50 per ton, in a range from $5.00 to $11.00 per known as the center of production. Railroad cars ton, depending on quality. Because of the many and trucks leave Ashfork daily with loads different products made in processing, wholesale consigned to all parts of the United States. prices here vary widely; small pieces of poor grade Geology and areal extent flagstone may sell for little more than $10.00 per ton, while special cuts will run more than $30.00 The Coconino sandstone is a uniformly me- per ton. dium-grained, well-cemented, generally pink, red, or white, eolian sandstone of Permian Age. As part Thus, it may be seen that in 1960, at least 85, of the Permian-Pennsylvanian Aubrey Group, this 000 tons of stone were produced at an average formation underlies the Kaibab limestone, and wholesale value of $21-$22 per ton. Coupled with overlies the Hermit shale and Supai formation. the retail business in Arizona, the State's stone in- Stratigraphically, its thickness is from 40 feet to dustry may be said to be well over $2,000,000 more than 400 feet. Thus, it underlies the entire gross. Coconino plateau in northern and northeastern Arizona. Extensive outcrops of Coconino sandstone

Old and newTower of Moenkopi sandstone, and new wall of Coconino sandstone.

9 are found in Mohave, Coconino, Yavapai, Navajo, seams to more than 20 feet thick, but within these Apache, and Gila Counties.11 However, due to its beds the arcuate cross-bedding is dominant. Thus, position under a hard, relatively resistant lime- in quarrying, thin sheets are split along these ar- stone, and over softer shales and sandstones, its cuate lines. A single zone of cross-bedding is out-crops do not generally cover the very broad some-times only 20-30 feet in length, but more areas of northern Arizona as do the Kaibab often the best quarries are in zones up to more than limestone and other formations. Although not 100 feet long. practical as producing areas, the most extensive Fractures across the bedding are not closely outcrops are in the rim of the Colorado River and spaced. Parting is generally fair to excellent, but its tributaries, crossing Coconino and into Mohave some massive zones 1-3 feet thick are present. Counties. The beds are well exposed at the Grand Most parting surfaces are smooth and nearly flat; Canyon. surfaces with ripple marks are sometimes found. Some of the more important areas of present Composition and physical character and potential production of Coconino sandstone are as follows: In Coconino County north of Se- The Coconino sandstone consists essentially ligman, the sandstone forms the slopes of Aubrey of rounded grains of quartz which are cemented by Cliffs under a capping of Kaibab limestone. Ap- silica. As a formation, other materials are present, proximately 10 miles northwest, north, and north- mostly as thin seams of clay minerals, mica, and east of Ashfork, Coconino sandstone is exposed or secondary silica, calcite, and gypsum. Inasmuch as under slight soil cover over more than 75 square these thin seams are usually culled in quarrying, miles. From east of Drake to the Oak Creek Can- the rock produced is an even-textured, quartz yon area, it crops out along the Coconino and sandstone. Of this rock, the silica content is Yavapai Counties border, where it forms the generally more than 90% and sometimes more than southern edge of the Colorado Plateau. In Yavapai 97%. Minor amounts of feldspar, mica, and iron County about 15 miles west of Ashfork it is ex- oxide are the most notable accessories; heavy min- posed over a few square miles near Picacho Moun- erals are present in academic quantity only. tain. In Navajo County, the Coconino sandstone Color variations are due largely to the quan- covers many square miles in scattered areas south, tity of iron oxide present. Gradations from white southwest, and west of Holbrook; exposures in through pink to red are dominant; such variations valleys tributary to the Little Colorado River are are broad in scale, both vertically and laterally. abundant. Less accessible are outcrops along the Thus, any single quarry usually produces only one Mogollon Rim in northern Gila County, and wide color with small variation. In some quarries, the areas southeast of Show Low in southern Navajo white tends to gray or to pink, and the red tends to and northeastern Gila Counties. The widest single tan, buff or to pink. Rarely, yellowish, purple, area of Coconino sandstone is in northern Apache lavendar, and even banded colors are found, but County on the Navajo Indian Reservation. Here, not in large quantities. the Coconino sandstone and DeChelly sandstone Porosity varies from approximately 7% to as are undiffrentiated. much as 19%. Moisture content varies from quarry Structure to finished stone; rock in place is usually damp, but tends to dry quickly on exposure. One sample of In general, and as a formation, the Coconino finished stone tested 0.3% moisture.* Compres- sandstone beds are nearly flat-lying. In places, sive or crushing strength is generally high, but may folding and faulting have created structural dips up vary according to cementing and weathering. Sam- to more than 45 degrees, but beds dipping steeply ples from the Navajo Indian Reservation tested is enough to create problems in quarrying are rare. from 2,225 pounds per square inch to 12,975 psi, However, this formation is noted for its intense with an average of 5,382 psi. However, three sam- cross-bedding. Stratigraphic beds are from thin ples of quality dimension stone* tested 14,795,

* Dunbar Stone Co., Ashfork, Arizona 013,450, and 13,993 psi. tion terminals, as well as quality of rock. Explora- Weathered rock, that is rock buried in soil or tion usually consists of finding an exposed bed of within a few feet of the surface, tends to be gray, if proper angles of cross-bedding in a wash or valley, or white at depth, and maroon, if red or pink at depth. It of bull-dozing the surface in timbered or soil-covered also is more porous, may be friable (crumbly), and is areas. weaker or lower in compressive strength. 2. Overburden or weathered rock is removed by Production bulldozing or simple quarrying; sometimes blasting is To the uninitiated, production of flagstone and done to develop a back seam to work toward. dimension stone from sandstone beds may seem 3. Approximately 4-inch thick sheets are wedged fairly simple. Most pieces of "float" seen on mile after and barred from in place. Massive beds unsuitable for mile of 'surface may be attractive for a stepping stone splitting are left as islands, or cut around and bull- or two in a garden or patio, but production of dozed to waste pits. specified sizes, consistent colors, and uniform 4. Sheets are split by wedging, and broken to strength, all in large quantities for demanding size for handling, and graded and stacked on edge. markets requires careful exploration, skilled Handling in quarries is aided by roller conveyers and quarrying, and efficient handling. Present practice is by rubber-tired, 2-wheel carts than can handle up to as follows: 500 pounds. 1. Prospecting for likely quarry sites. Consid- 5. Graded rock is loaded on flat bed trucks and erations are accessibility, terrain, and transporta hauled from quarries to cutting yards. Grad-

Arcuate bedding in Coconino sandstone beds rise to right and left of truck in bottom of "trough".

11 ing in quarries is by size, color, firmness, smooth- surface. Power is applied, and the teeth snap the ness, lack of scale, etc. Some operators market their stone, creating a "split face." Eleven of these cutters products at this point, hauling to dealer's sales yards of different capacities are now in use in Arizona. or to consumers in cities, or selling by contract to 7. Finished stone is again graded by cut di- cutters who further process the stone; sales are by mensions and stacked on pallets, bound with steel weight. tape, and in some cases covered with paper or plastic. 6. At cutter's yards, the stone is again sorted, graded, Palleted stone is stored in yards, then loaded on sized and cut to dimension. Cutters are the "guillotine" trucks or railroad cars for shipment to dealers, or type, hydraulically operated. Flat sheets of stone up direct to jobs. to 12 inches thick, and as much as 5 feet in longest 8. Flagstone is often transferred from quarry dimension, move under the cutter blade on rollers. trucks to docks, and then loaded direct to cross- The cutter consists of a row of "teeth", each powered country trucks or railroad cars for shipment. separately, which are lowered in unison to the surface 9. Recently one operator installed a wire saw. of the stone. The individual teeth fit any irregularities Massive pieces unsuitable for splitting, are rolled in the

Quarry in Coconino sandstone, showing wedging, waste, and stone stacked for shipment.

Guillotine stone cutter in quarry of Coconino sandstone.

12 13 under the saw on tracks. A continuous, Costs multiple-strand wire on large reels runs over the Under present conditions, and granting con- slab immersed in abrasive grit, cutting large, siderable variation between different operators, thin sheets. the proportions of costs for extracting and In order to meet quality demands, the above processing Coconino sandstone are production procedure involves considerable approximately as follows: waste. Approximately 1/3 of the rock handled Quarrying 30% in the development of a quarry is culled into Haul quarry to yard ------9% waste or "muck" piles. During quarrying 2/3 to Cutting, grading, packaging ------30% as high as 80% of the rock handled is wasted Haul to destination (customer) off. At the cutting yard, again about 1/3 of the Overhead, development, profit ------31% rock brought in is ultimately waste. some operators say that after a quarry is developed Specifications, products, trends in use and is operating efficiently, the waste rock can The qualities that make Coconino be held to 60% of the total handled. sandstone popular are due to several characteristics that make it an excellent Shipping building stone. First, of course, is its lasting Coconino sandstone is shipped by both rail-road natural beauty. Attractive colors are avail-able, and truck. A main line of the Atchison, To- and coupled with its general linear form the peka, and Santa Fe Railroad trends east-west stone is highly adaptable architecturally. The across the state, and through major areas of popular, informal, rustic effects may be stone production. The largest rail shipments attained, as well as the more formal are made from Ashfork and Williams. Most of requirements of public buildings, churches, and the stone destined for points in Arizona is office buildings. hauled by truck. Also, large quantities are Physical characteristics of this stone also make shipped out of the state via truck. particularly it desirable. It is durable, it does not contain to the west coast. minerals that oxidize or weather, causing Some Coconino sandstone producers prefer stains, it can easily be kept clean, and it can be shipment by rail, but customers often prefer cut to clean edges. Moreover, it competes well truck delivery. Trucking allows for "back door with brick and other manufactured materials in delivery" to individual jobs or to dealer's close tolerance to dimensions. One producer is yards, and obviates double handling. In marketing 117 sizes, with thickness of 1/ 16 addition, large dealers in construction materials inch intervals. Either, or both split faces and may haul with their own trucks, and some parting surfaces may be ex-posed. Special trucking companies are also in the materials orders may be filled to the most ex-acting business. The larger producers ship architectural needs. Flagstone in large sheets is approximately equal amounts by truck and rail. desirable for particular purposes. Thus, variety Loads are. of course, larger on railroad cars. ( itself allows a wide range of uses. See discussion of transportation and freight Prior to World War II, only small amounts rates be-low.) of dark red, weathered, surface rock were Currently. approximately 70% of Coconino available; the unweathered rock beneath the sandstone produced is shipped to the west soil had no value. This flagstone was used coast. particularly to Los Angeles. San primarily for very rustic settings, and although Francisco, and Seattle. About 10% is used in considerable amounts are sold today, the trend Arizona, and 20% goes to midwest and eastern in quantity has been to semi-formal uses. As markets. Some is being shipped as far as the Coconino sandstone be-came popular, a Alaska. Canada, and Hawaii. With only the ' basic change in stone use was taking place. post-war period of development, Arizona s Due to new developments in use of steel and Coconino sandstone is becoming well known cement, demand for stone blocks for structural throughout the United States. purposes was supplanted by a much greater need for decorative veneers, facings, and

14 Stationary wire saw cutting Coconino sandstone. urn. Specifications became more rigid. In order to marketing sized and color-grade granules for roof- meet both design and structural needs, new produc- ing. tion techniques from quarry to final delivery had to be devised for this stone. Thus, grading in quarries Problems assures firm, smooth-surfaced rock of consistent Some of the problems facing the sandstone in- color; the new, multi-toothed, guillotine cutter makes dustry in Arizona are normal to the growth of any cleaner split faces; close tolerance in thickness new industry. Developing new markets and new allows designers freedom and promotes speed and products, meeting more and more rigid specifica- efficient use of material by masons. tions, and developing research are common needs. As a result, products now being produced are other problems are peculiar to Arizona's sandstone numerous. Large and small operators produce flag- industry: stone in a variety of colors, thicknesses, and grades. 1. A skilled labor force has had to be created. Cut stone is produced in thickness from 1/2 to 12 ' inches, and in forms for ashlar strip for veneer, for The State s small population, and location remote treads, sills, lintels and copings. Table tops and large from traditional stone producing areas conspire to sheets are available. Broken stone is available for provide few experienced stone workers. As informal landscaping. Colors may be matched, and fluctuating markets are becomin stabilized, working special orders for extraordinary products are conditions are becoming better. solicited. At least one company is packaging do-it- 2. Handling of waste is a problem that will yourself kits of stone cut to dimensions suitable for eventually be reduced, possibly by new by-products, building home improvements, such as barbecue or by mechanization, or by improved quarry tech- fireplaces and planters. At least one company is niques. At present, demand for high quality forces high waste factors on most operators.

15 3. Mechanization has had to grow with the Moenkopi sandstone deposits along the rail- industry and markets. A few years ago, nearly all road from Flagstaff to Holbrook have been quarried work was done by hand. Today, light and some extensively. This hard stone commonly caps mesas, heavy machinery are used. As the industry grows, making quarrying somewhat easier. Deposits on the the eventuality may be machines designed expressly Navajo Indian Reservation are reported to be good for handling Coconino sandstone. for dimension stone. 4. Improvement of products is a continuing DeChelly sandstone problem. Although a certain amount of sandstone In a description of dimension stone on the Na- will always be demanded for its unique characteris- vajo-Hopi Indian Reservations, H. Wesley Peirce tics, volume production and sales will depend on gives considerable data on the DeChelly sandstone ( meeting competition of brick, artificial stone, alu- Permian) . Comparisons are made with the Coco- minum, glass and other materials that may be sub- nino sandstone. Regarding stone as a whole in this stituted for stone in designs. This means primarily area, he reports, "Of the sandstone deposits, the holding costs down by efficient production, and upper unit of the DeChelly sandstone offers the best making a product that may be installed easily and potential for a good commercial stone." cheaply. 5. New exploration techniques are needed to MARBLE provide good quarries. Again, as the industry grows, capital will become available for more thorough Occurrances of marble as a geologic rock type field exploration, and research may develop criteria are numerous but widely scattered in Arizona. Many for choosing quarry sites. varieties are available, and many deposits have had intermittent production. Past production includes saw In the total picture, none of the problems blocks and polished slabs, but current production appears insurmountable. Resourcefulness, determi- consists almost entirely of crushed marble for nation, and dedication to quality have already made terrazzo, roofing materials and exposed aggregate. the Coconino sandstone famous. Operators have Increased markets, and the installation of modern confidence in their raw material, and end users have extraction and processing facilities could make confidence in the products. Arizona marble compete favorably with any other Moenkopi formation source of this traditionally elegant stone. Due to the variety of types of marble and of Sandstone from the Moenkopi formation (Tri- geologic settings, neither a general description such assic) has been used extensively for construction in as for the Coconino sandstone is sufficient, nor are Northern Arizona, and has been shipped out of detailed descriptions of individual deposits appro- Arizona as building stone. The Moenkopi formation priate here. Therefore, the following consists of is exposed over wide areas in Navajo and Apache pertinent general features, with some detail con- Counties," and in northern and eastern Coconino cerning certain regions having common character- County. It consists of uniform shades of maroon and istics. chocolate-colored sandstone and shale beds. The Geology and Areal Extent sandstone occurs in beds from a few inches to several feet thick, separated in places by thin partings up to Geologically, marble deposits are generally treated thick beds of shale. The sandstone is generally as a part of limestone and dolomite stratigraphy. massive within beds, and does not split easily, as That is, the basic sedimentary units are limestone and does the Coconino sandstone. Although vertical dolomite, and these have been more or less jointing is common, large blocks may be quarried in metamorphosed to marble. In some places, the places, and the stone may be cut and shaped. Fairly metamorphism is local, creating small and ir- new buildings on the campus of Arizona State regularly-spaced marble deposits, and in other places College at Flagstaff are made of sandstone from the the marmarization is continuous and wide-spread. Moenkopi formation. The type of marble in any deposit is due

16 Recent use of Moenkopi sandstone. essentially to first, the nature of the original for- rock. It may be colored, possibly with several mation, its composition, bedding, intercalated lay- hues, veined and streaked with new minerals, or ers such as shale and sandstone, fossils, and struc- the original rock may have been fractured and the ture. Secondly, the types and intensity of meta- fragments cemented by a metamorphic matrix. morphism determine the character of the marble. Thus, the more abundant the variety of original Thus, if a pure limestone, white and without inter- and introduced minerals, and the more intense the calated beds of shale or sandstone, has been sub- crustal movement, heat, and pressure, the more jected to folding (dynamic metamorphism) only, complex in color and texture the marble will be. the mineral calcite (CaCO3) making up the lime- It may be seen that the more varigated mar- stone may be recrystallized to a white and other- bles have undergone severe changes that obscure wise featureless, massive marble. On the other the original character of the limestone formation. hand, an impure limestone, perhaps dolomite9 ( Age correlations are, therefore, difficult at best. In CaMg(CO3)2,) containing iron and other colored Arizona, although some Cretaceous limestones are oxides, and containing shaley and sandy partings locally marmarized, the bulk of the marble de- or beds, may have been subjected not only to posits are Permian to Devonian in age. In some folding and faulting, but to intense thermal cases, early detailed dating has been abandoned metamorphism, and metmorphism created by the for the general age of Paleozoic undivided," or introduction of other materials through veins or even Paleozoic and Mesozoic undivided. Also, it impregnation by solutions. Here, obviously, the may be seen that contrary to the consistently simi- resulting marble will be greatly different from the lar geologic settings of deposits of Coconino sand- original

17 stone, marble deposits are likely to vary greatly even dimension. The dark, reddish-brown portion is mostly in the same region. dense, fine-grained, and tough, probably with some Marble deposits are particularly abundant in the silification. The colored facies are fine to coarse- southern and western parts of the state. De-posits that grained, dense in small units, but tend to part along have been exploited, although not all inclusive, may veins and micaceous bedding planes; they have a be grouped roughly as follows: frosted appearance in both fresh fractures and 1. Harquahala Mountains polished slabs. 2. Tucson region 2. Tucson region. 3. Dragoon and Chiricahua Mountains Deposits of white marble are being exploited 1. Harquahala Mountains, including the Little north, southwest, and southeast of Tucson. In Pinal Harquahala Mountains. County, north of Tucson and about 5 miles southwest of Oracle Junction, a small area of coarsely- Here, Paleozoic and Mesozoic limestones have crystalline marble dated with Carboniferous and been locally marmarized in a zone trending north-east Devonian formations occurs on Precambrian granite from about 10 miles southeast of Hope in Yuma country rock; the total area of the marble deposit is County, across the boundary and into Maricopa less than one square mile, but substantial reserves County to about 12 miles southwest of Aguila. In a are present. Original bedding and stratification have country rock of granite, gneiss, and schist, been lost. As deep as present workings show, the pure sedimentary beds have been altered to marble and white, dense rock is fairly highly fractured. quartzite largely by metamorphic action related to Cretaceous andesitic volcanics, and diabasic dikes. Approximately 30 miles southwest of Tucson, Probably the best exposed marble, and fairly along the west side of the Sierrita Mountains, Pale- representative of the area is in a zone on the north- ozoic beds are present in northwest trending bands. west side of the Harquahala Mountains, where The formations are up to mile wide and extend over limestone with intercalated shale seams and limey more than 8 miles. Marmarization has generally sediments have been folded and faulted and intruded produced a massive to highly fractured, fine to by basic material. Irregular masses of dark gray, dark coarsely crystalline, white to gray marble, being brown, and reddish brown, veined marble are present exploited for roofing and other crushed rock uses. together with irregular masses or large blocks of The geology of the Sierrita Mountain region is white, pink and green marble. On the weathered complex. The Paleozoic beds lie within an area of surface, the former is dark brown, while the highly- Cretaceous sediments and granitic intrusions. These colored marble is largely a dirty white or gray color. have been affected by intrusion of both Cretaceous Production in the area appears to have been and Tertiary lavas which, together with intense concentrated on the brightly-colored stone. This is faulting, further complicate the picture. Nevertheless, probably dominantly white, but is colored pink and in any one locality, the geology of substantial green near veins and dikes. Metamorphism pro- deposits of marble may be determined. gressed away from the intrusive features, largely In areas currently being worked, pure white mar- along original bedding planes. The resulting stone is ble is sought. Exposures show considerable variation vari-colored; in places is consists of alternating pink, in color, texture, and fracturing. Discernible bedding green and white beds of various thicknesses from less is fairly regular, but fracturing is also fairly intense. than an inch to more than one foot thick, and in other The rock breaks along what may be bed-ding planes, places a mottled pink and green is present. Some of with beds being 2 inches to 2 1/2 feet thick and an the original shaley seams have been converted to a average of about 9 inches. Iron stain and some pale greenish-gray mica. pink and green zones are present. In addition, This attractive rock appears to he localized in apparently discontinuous sandy and shaley facies are large blocks, at most several tens of feet in longest present. The white marble is re-

18 ported to be a very high lime rock. 3. Dragoon and Chiricahua Mountains area. Approximately 27 miles southeast of Tucson, Perhaps the best known marble deposits in and 6 or more miles south and southeast of Moun- Arizona occur in Cochise County at the north end tain View, other deposits of white marble are of the Dragoon Mountains and the north end of the being exploited. Here again, Paleozoic beds occur Chiricahua Mountains, grouped here because of in complex structural relations with Cretaceous proximity and common historical development. In sediments, and with younger granite and diorite 1909, L. R. Ligier, the pioneer marble prospector, porphyry intrusions; some of the marble may be stone mason, and stone sculptor, staked claims for Cretaceous in age. Dirty-gray on the weathered marble on Federal land in both areas. Due to claim surface, the marble is brilliantly white, and is jumping, bitter litigation ensued. In the 1920's, medium to coarsely crystalline in fresh exposure. after the death of the far-sighted pioneer, the Fracturing is fairly intense, but none of the claims were perfected. quarries extend to very great depth. At the north end of the Chiricahua Moun- In the northwest corner of Santa Cruz Coun- tains approximately 15 miles southeast of Bowie, ty, about 3 miles east of Amado, Paleozoic beds deposits of massive, white marble with dark veins include another deposit of white marble that has occur. Here, Cambrian beds of Abrigo limestone, been quarried in the past. The areal extent is not Carboniferous and Devonian beds, and Cretaceous great, but local reserves may be large. Here, the sediments have been folded and faulted into com- Paleozoic beds have been intruded by a Laramide plex relations with Precambrian granite and schist. granite. The marmarized rock is fairly widespread, with

Outcrop of colored marble near Wendon.

19 large reserves. The stone is mostly dense, massive, Composition and physical character and moderately free of fractures. In the Harquahala region and the Dragoon and Spectacularly-colored marble occurs at the north Chiricahua Mountains, the marble is so varigated in end of the Dragoon Mountains, southeast and color and texture as to lack consistent chemical northeast of Dragoon. A number of quarries have composition. Doubtless, analyses of the highly been opened here, and are scattered over an area of metamorphosed rock would show high ratios of more than 10 square miles. Granting some variation silicon. magnesium, iron, etc., to calcium carbonate. within quarries, in general a single color or pattern However, an analysis* of white marble fines from a may be produced from a particular de-posit. crushing operation near Dragoon is as follows : Available colors are black, white, pink, green, CaCO 98.00% maroon, gray, cream, black with gold colored veins, 3 SiO, 0.62% shades of yellow, a combined gray and gold, and a MgCO 0.39% gray and vari-colored, fossiliferous breccia. In R O 0.80% addition, a "Serpentine marble" said to resemble onyx 2 3 has been reported. 99.81% Also, the white marble in the Tucson region is In this region, the structure and metamorphism " " of the marmarized beds are particularly complex 12 generally pure consisting of 97 percent or more of Paleozoic limestones and dolomites of the Naco calcium carbonate. Group, together with Cretaceous sediments (Bisbee The composition of the highly-colored, veined, formation) are intensely folded and faulted, and have and varigated marbles in the Dragoon Mountains, is been intruded and otherwise affected by Tertiary complex, by virtue of the new minerals created by granite, dikes and other igneous rocks. Structurally, metamorphism. Basically, the original limestones and the sedimentary formations are tightly folded dolomites contain impurities of quartz, iron oxide, anticlines and svnclines with axes trending north and and clay minerals. High temperatures and the northwest. In places, limits of the folds have been introduction of new elements from nearby igneous sheared by faults trending roughly parallel to the intrusions have created a number of metamorphic fold axes; cross faults are also common. This minerals. Part of the green color is due to chlorite, an complex of sedimentary rock is bounded on the south hydrous silicate of aluminum, magnesium and and northwest by Tertiary granite and other igneous ferrous iron; and green, reddish, yellow, and even rocks which probably also underlie the sedimentary black colors may be due in part to serpentine, an rocks at shallow depth. The metmorphic effect of the hydrous magnesium silicate. Mica of various colors is young intrusives, together with the intense tectonic also present, and wollastonite, a calcium silicate is deformation, has been to alter the original rocks reported in some of the marble; rarer minerals such nearly beyond identification and correlation. The as lime garnets further complicate the composition. combination of impure (shaley and sandy) carbonate Of course the ubiquitous oxides of iron are rocks, intense metamorphism of all kinds, and responsible for much of the col-oration, including not introduction of plutonic materials has created the only shades of red, but yellow, green, brown, purple, present, highly-varigated in color, veined and and black and cream. patterned The attractiveness of the stone is enhanced by marble. Bedding and stratification are esentially the colors and textures, streaks, bands and patterns absent, faults and fractures have been filled and created by metamorphism and the attendant min- recemented with metamorphic minerals, and in erals. But large amounts of these minerals may places, brecciated rock is suspended in matrix of weaken the rock, complicate cutting and polishing, marmarized limestone. Only detailed study of the and causes pitting and staining in use. In both the area can yield an accurate and complete description Harquahala and Tucson regions, the marble is firm of the rocks. and dense in small fragments up to as much

*Courtesy of Mr. D. G. Ligier, Dragoon, Arizona

20 as 2-3 feet in longest direction. But present quarry loaded on trucks and hauled to the railroad for faces show fairly closely-spaced fracturing and shipping. Attempts were made, to make blocks ap- jointing. This may be due to current quarrying by proximately 6 feet long and at least 2/2-3 feet in blasting for granule production, or to the fact that width and thickness: smaller sizes are acceptable, few, if any quarries have been exploited to depths but less desirable. well below the weathered and fractured surface The cost of quarrying marble saw blocks can material. In the Dragoon and Chiricahua Mountains vary widely, due largely to the waste or recovery saw blocks more than 6 feet in length, and a factor. After a quarry is well established, a basic minimum of 2½ - 3 feet in thickness have been pro- cost of $1.50 per cubic foot is expected: larger duced in quantity. Here too, the quarries have not blocks not only cost less per cubic foot to quarry, been developed to depths assuredly below the but bring better prices. Colored marble should sell weathered zone. Deposits near Tucson are being for $7.50 per cubic foot up - $15.00 per cubic foot worked primarily for crushed stone for roofing, ter- would probably be normal in standard blocks. 10- razzo, plaster, etc. The purest white reflective stone 10½ square feet of slab or sheet marble are ex- is sought. Thus, sandy and clayey seams are avoid- pected from 1 cubic foot. After polishing, prices of ed, but in places the accompanying iron stain causes colored marble are in the magnitude of $4-12 per rejection of gray and yellowish stone. square foot. The weight of the Arizona marbles is neither Today, the only marble being produced for heavier nor lighter than normal. Dragoon marble. cutting and polishing is in small blocks which can be presumably originally dolomitic and containing cut and finished on light equipment. Small pro- heavy accessory minerals, has been tested at 186 duction for copings, fireplace fronts and special jobs pounds per cubic foot. High lime marbles made is reported from several areas, including the quarries dominantly of calcite, may be as low as 170 pounds of pink and green marble near Wendon. per cubic foot. The bulk of today's marble production in Ari- Production, products, shipping, and costs zona is granular or crushed stone. Nearly all of the Two general types of construction materials active quarries in the Harqualhala, Tucson, and have been produced from Arizona marble deposits; Dragoon-Chiricahua regions have at least intermit- one, cut and polished slabs, sheets and blocks, and tent production, and quarries in several other areas two, granular materials for roofing, terrazzo, plaster, are reported to have had substantial production in copings, exposed aggregate, and landscaping. the past. At least 4 plants are producing regularly, if By far the largest part of the marble produced not continuously. for cutting and polishing has come from the Dragoon and Chiricanua Mountains. As much as 4,000 tons is After prospecting by examination of outcrops reported to have been produced in this area around and bulldozing surface material, production of 1950, when substantial production of saw blocks was crushed marble entails first removal of overburden. attained. The blocks were shipped to California, Most present quarries are on hillsides, where over- Missouri, and New York, and as far as Canada, where burden is light and can be pushed to lower eleva- they were cut, polished, and finished to flooring, wall tions away from actual quarry sites. This is followed facing for store fronts, fire-places and interiors and by air drilling and blasting, with heavy charges to monuments. No large-scale, permanent cutting and induce fragmentation. Broken rock is moved by polishing mills have been established in Arizona. front-end loader to a truck which hauls to a grizzly. One operation includes a shaker screen under the Saw blocks were produced by first clearing a grizzly to remove fines, clays and dirt. Another face in firm rock. Then pneumatic drills (drifters) on operation uses a dragline to remove broken stone rigid quarry bars cut rows of holes on all sides, from the quarry to a truck loading arrangement. followed by broaching, and the blocks were From the grizzly, the stone is truck-hauled to proc-

21 essing plants. Processing usually consists of Arizona and California, with eastern markets be- passing the stone through a grizzly, through ing developed. primary jaw and secondary roll crushers, screening to size with return of oversize, and bagging. With For the two basic uses, prices F.O.B. plant are this general process, specifications are considered approximately: easy to meet. White Colored Granules are produced in all gradations from Roofing granules $15-18/T $19/T fines to 2 inches in size. Larger pieces, including Terrazzo $15-19/T $22-30/T rubble are produced for masonry and landscaping. The bulk of the white marble of the Tucson area is Costs of producing crushed marble vary ac- produced for roofing granules which have a high cording to types of operation, haul, and waste. insulation factor through reflection; white terrazzo Quarry waste varies considerably, being 2-5% in chips are second in demand. 65-70% of the colored established colored stone quarries, and as high as marble from the Dragoon Mountains is used as 35% in relatively new white marble operations. terrazzo, with roofing material demands being sec- Processing waste is about 15%, including 2% culls ond. Considerable colored, rough marble for wall and 13% powder. Powders are generally saved for work and decoration is produced. Other uses are possible future use. growing, but are currently minor. Much of the Reported quarry costs vary from $2.00 to $4. Tucson area marble is consumed in Arizona, with 50 per ton, and processing is about $9.00 per ton. some shipment to the west coast. Destination of the Truck haul over rough roads for any appreciable colored marbles is about evenly divided between distance may be as high as 10¢ per ton-mile,

Serrated quarry face due to removal of marble saw blocks.

22 with haul on pavement being 5¢ - 7¢ per ton-mile. A roofs has grown with the development of low angle breakdown of average costs is summarized: roofs. Here the architectural trends probably determine most of the demand; likewise for marble granules used as exposed aggregate and in copings for swimming pools and other structures. For marble used as dimension stone, there is a reawakening to the adaptability and beauty of this ancient stone. Few rock types are easier to cut, and no polished surface can exceed the interest of texture, pattern, and color. This, together with high durability and strength, and low maintenance. make it fitting for most decorative architectural requirements. Arizona marble can compete in quality and beauty with the best European sources. Moreover, it is one of the few highly colored and patterned Specifications and trends marbles in the western hemisphere. Varieties are exceeded only by the reserves, of which colored Presuming availability of colors, the require- stone alone are in the hundreds of million of tons. If ments for crushed marble are few and can be met. less than 1/10 of estimated reserves are suitable for Sizing must be accurate, the particles must he clean cutting and polishing, more than 7 square miles could and free of powder, and colors must be consistent be covered with marble, each square mile with a and not subject to stain. different color or pattern. On the other hand, specifications for dimension Problems stone, monuments, and statuary marble are far more rigid. The stone must be firm, cut smoothly, take a Because of differences in production tech- high polish, and have consistent color, veining niques, products, and markets, the problems of in- patterns, and fossil and breccia distribution. It must creasing and stabilizing crushed marble production be free of minerals that weather to pits, holes, or are considerably different from those connected with stains. Statuary and memorial marble must be free polished marble. of any structural flaws. Unless vein patterns are Techniques for quarrying and processing desired, specifications for white marble slabs crushed marble are fairly well established for mod- include freedom from stains, discolorations, and est production. The primary goal at this point must be veins and cracks; closer attention is given to firm- increased markets. Larger demand for terrazzo, 'mop ness than with highly-colored and textured stones. down' roofs, and exposed aggregate in construction Traditionally, marble chips have been used for will require the greatest increase in production. terrazzo. Experiments are made with other ma- Substantial increases in production will provide a terials, but to date no substitute or alternate has basis for more mechanization and eventual lower provided serious competition. The infinite design prices for products. Stability will accrue only when possibilities of terrazzo are beginning to capture the products are consistently competitive with other builder's interest as their demand diminishes for the building materials. In addition, methods should be quick, cheap, rudimentary construction that devised for more accurate exploration of deposits. In followed World War II. Also, more efficient grind- some quarries, extraction costs are unduly high ing and polishing equipment, as well as the pre- because new production sites must be found before casting of both slabs and shaped units should re- an optimum amount of material has been removed, duce costs. Cost of terrazzo chips could be substan- Geologic examination, coupled with exploratory tially reduced by larger volume production at quar- drilling of properties could remove much of the ries and procesing plants. hazard of unanticipated shaley, sandy, The use of marble granules for "mop down"

23 24 24 and stained zones. Also, more consistent rock, al- unmitigated success, and from colonial days to the lowing closer quality control may be found at greater present. Early settlers in Arizona found it not only depths below the weathered zone. convenient to produce, but particularly functional as Renewed production of Arizona marblc for an insulation from severe heat and cold. As with all polishing will consist, in essence, of starting a new building stone, for a recent period its quality has been type of industry in this area. with problems of de- overlooked in favor of the novelties of more modern velopment of deposits and production techniques, materials. But the combination of increased creation of markets, and meeting present day speci- population creating markets. new production fications. techniques. and architectural fashion trends should The problems may be grouped as follows: renew interest in Arizona's excellent deposits of tuff. 1. Proper choice of deposits to be worked, based Terminology and general geology on geologic examination and drilling, must Specifically. and geologically, the word tuff be made to insure adequate re-serves and refers to cemented volcanic ash; a pyroclastic rock.13 efficient production with the least waste. 18 Variations include tuffite, a general term applied to This may require some development work rocks containing not only ash, but also other detrital to obtain stone from depths below surface material both volcanic and surface in origin. Tuff weathering. breccia includes fragments that are much larger than 2. Financial requirements will probably be ash. In a welded tuff, the particles have been large, relative to other stone operations. The indurated or consolidated at least in part by retained built-in difficulties attending small-scale volcanic heat and gases. If, during its origin, the extraction operations in today's economy tuffaceous materials flowed, the resulting rock is a are well known. Indeed, it is probable that tuff lava, and may be known as an ash flow. A the only successful production will be common misuse is the word tufa or tufa-stone, which obtained by an operation including not only properly applies to the cellular, calcareous sinter or quarrying of saw blocks, but cutting and siliceous sinter deposits of mineral springs. Most polishing and marketing the stone for final Arizona deposits of tuffaceous material having a use. Mechanization is essential, and the use potential as building stone would more accurately be of the latest and best production techniques, called tuffite, tuff breccia or welded tuff, as the case such as wire saw quarrying of blocks, is may be, but for general use the term tuff is practical. indicated. Tuff deposits have their origin in volcanic ac- 3. Standardization of shapes and sizes is es- tion. The many varieties are understandable when the sential, in order to compete with other complexities of volcanism are considered. During materials in cost of installation. Large de- eruption of a volcano, not only is lava usually mand is most likely to come from building emitted, but solid and semi-solid fragments, bombs, and other construction, where the choice of dust, cinders and ash, as well as water vapors and materials to be used often depends on the other gaseous materials are ejected, all at various ease and speed of handling. temperatures. Sometimes these materials are ejected simultaneously, and at other times only one at a time. TUFF Also, as these materials come up through the earth's crust, they may break off and carry with them large Tuff may be considered at this time as a and small fragments of other rock. Finally, after neglected stone. Yet its unique characteristics give it being deposited, the materials may be shoved, a potential of becoming a standard construction reheated, fractured, covered, or intruded by other material in modern practice. Being light in weight volcanic ejecta. Arizona was an active and easy to shape, its history as a fundamental building material is ancient in many parts of the world. It has been used extensively in Mexico with

17 volcanic area from some time in the Cretaceous compensated in part by higher strength; the period into the Quarternary period. Therefore, aver-age compressive strength of this tuff is the resulting deposits visible today are probably well over 5,000 pounds per square generally complex in size, composition and inch, and may be more than many competent structure. sandstones. Porosity-permeability tests of two Character of representative deposits samples show the volume of water absorbed per volume of rock to be 9.7%' and 4.4%. This Deposits of tuff are numerous in Arizona. tuff is generally massive, and will yield large They are, of course, associated with other saw blocks. It may be cut with ease with a volcanic rocks that are scattered throughout the diamond saw, and quite adequately with a state. The range in area of deposits that have carborundum saw. been worked is from north of Kingman to south of Wendon on the west, and from north of Holbrook on the east to the southeast corner of the state. Only deposits representative of areas or types are discussed here; many others of equal quality and potential exist. On the Navajo Indian Reservation in central Apache and Navajo Counties, deposits of tuff in the Bidahochi formation (Tertiary) are common. These are ably described in Mineral Resources, Navajo-Hopi Reservations. Arizona-Utah,16 and are reported only generally here. At least three dozen deposits of tuff are reported. The tuff beds are mostly whitish-gray in color, are 2-6 feet thick, contain some clay and sand beds, have a wide range in A third notable area of tuff is the vicinity of chemical composition, and consist dominantly San Carlos in southeastern Gila County and (70-85) of glass shards (ash,) with the north-western Graham County.4 Considerable remainder "being quartz, feldspar, hornblendes, " production has been reported from several rutile, glass and garnet fragments. the stone is deposits in this area characterized by Tertiary light in weight. fine-grained and porous; the and Quaternary volcanics, particularly basalt. grains and fragments are not tightly bonded, The tuff is mostly fine-grained, white to gray, but compressive strengths of 2,000-3,000 with some pumice and andesite pebbly pounds per square inch are reported. fragments. In places the "pebbles" are stratified in zones. The material reportedly de In the southeastern corner of Cochise velops a case hardened effect with prolonged County, tuff deposits are associated with exposure. It cuts easily into large blocks, and Tertiary rhyolite (lava.) In one area, a welded, has been used with considerable success. porphyritic, rhyolitic tuff (see analysis below) In the vicinity of Clifton, Greenlee County, is present over at least 150 acres. The stone an off-white tuff, largely free of "pebbles" is occurs in colors of white, a sand-colored huff, easily carved and has been used locally with and a soft pink. The colored matrix is dense, success. fine-grained, well-bonded and en-closes At Canyon Lake on the Salt River, crystals of sanidine, biotite and magnetite, as Maricopa County, a generally buff-colored, but well as fragments of tuff and siliceous also gray and white tuff with fragments of material. andesite and rhyolite has been in intermittent Density measurements of two samples of production. this tuff are reported to average about 2.1, Another notable area of tuff is near which gives a weight of approximately 131 Kirkland in Yavapai County, where deposits pounds per cubic foot. Other samples are said to associated with

* Courtesy of Mr. D. G. Ligier, Dragoon, Arizona Tertiary and Quaternary basalt have been operated biotite, feldspar and quartz are present. intermittently since before 1900. The deposits are irregularly distributed over an area of perhaps a Also in Mohave County, about 5 miles south- square mile, and extend to depths of 100 feet in east of Wickieup, a green stone classed as tuff is places. notable. Although reserves are not large, the stone is unique in its soft, apple green color, and that it is The stone is consistently light gray in color, and opalized and otherwise silicified. It occurs as a bed is composed of a fine-grained matrix of glass shards, 8-12 inches thick, included in Quaternary basalts, enclosing small but easily visible quartz and sanadine with overburden up to 50 feet consisting of tuff and crystals, and including fragments of dark volcanic altered tuff. The stone is hard and dense, with rock. The latter fragments range in size from tiny to varigated bands of shades of green. Current pebble and cobble size; they are not evenly production is under way. distributed, and in places form strata or beds, giving Production the stone a pebbly appearance. The dark fragments are mostly obsidian and aggregates of glassy Much tuff has been used locally in Arizona over fragments. many years. In 1909, Schrader20 wrote, "The most important building stone in the region is the rhyolitic The stone is not as firm and well-bonded as tuff underlying Kingman Mesa." and, "The most some other tuffs, but is correspondingly very light in important buildings in Kingman are built of it." The weight. Its compressive strength has been tested at 3, production history consists of intermittent operation 200 and 3,400 pounds per square inch, and its weight of many quarries; therefore, production data are is 88-115 pounds per cubic foot. It is, of course, scant and inaccurate. Tuff has been exported from highly porous, and its insulating character has been Arizona in considerable quantities, but not sufficient found by long experience to be very good. to sustain continued production. A tuff deposit notable for its unique colors is located on the northeast side of the Eagle Tail Recently, more than 33,000 square feet of Mountains, Yuma County. Called "mint stone," the curtain walls in additions to the state capitol were rock in general has a unique soft green color, but also made of tuff; 8 to 10-ton saw blocks were quarried includes bands of lavender, purple and white near Kirkland, and hauled by truck to a Phoenix material. The bands range from fractions of an inch cutting yard, where a sand and water saw cut rough to more than a foot wide, and are composed slabs that were trimmed by diamond saw. Currently, individually of dense, massive, welded ash to beds some quarries are being worked for rough stone for composed dominantly of very coarse fragments of wall facing and landscaping. Also, substantial " purple, black, and maroon-colored volcanics with a quantities of the green colored "mint stone have small awount of fine-grained matrix. Fairly large been quarried since World War II. Thus, although reserves are available, but are limited by complex one quarry operator believes that tuff can be structure. The tuff beds apparently lie between lavas, produced for about one-third the cost of marble, and the whole sequence has been faulted, tilted, and production has never been stabilized on a continuous intruded by other volcanics. Thus, the beds of tuff are basis. blocky, and are not continuous over great distances. Problems Intermittent production is carried on. Two problems are fundamental to growth of a In the vicinity of Kingman, Mohave County, tuff stable production of tuff. First, larger markets for was quaried in years past for extensive local use. The slabs and dimension cut stone must be developed. stone is largely a light-colored reddish pink, with Tuff is a relatively unknown rock type, and its " some dark to black zones. It is medium-grained and characteristics as a building stone must be called to 20 fairly uniform in texture and dresses well." Small, the attention of builders and designers. Its con- but distinguishable phenocrysts of tinued, successful use in comparatively small quan-

29 Massive tuff.

tities over the years is not sufficient advertising in The second fundamental problem is to establish today's rapid and highly competitive building econ- operations consisting not only of quarrying, but also omy. All building stones have some disadvantages; of milling and finishing. As in the case of marble, and these must be studied with a view toward integrated production from quarry to market holds overcoming them, or circumventing them with proper the most promise of stable success. Not only is there design. Below is a general evaluation of the an obvious financial advantage in an integrated characteristics of tuff : operation, but techniques of production may be improved; detailed characteristics of a particular Advantages* Disadvantages* rock may be learned in the quarry and passed on to Light weight Low tensile strength the benefit of cutting and trimming operations. Also, lower shipping cost Permeable stocks of various sized dimension stone may be built ease of handling high absorption up, and special orders are easier to fill if quarrying light weight construc- may be weakened b} and processing are integrated. It is not too visionary tion freezing when wet to conceive of a cutting and trimming yard being High insulation quality Will not take polish supplied saw blocks from a number of quarries, in Variety of colors Some deposits thin and order to market a greater variety of products. Variety of textures or small In addition, mechanization is essential. Wire Can be worked easily saws requiring little attention can be adjusted to saw Can be cut to dimension block production and slabbing; handling of saw Compressive strength blocks must be systemized. Quality control adequate to high Low production costs

* It should be noted that some features create both de- stone may be permeable and have less strength. Also, not- sirable and undesirable characteristics. For example, the able is the variety in character of various deposits; if low more porous types of tuff are very light in weight and are permeability is needed, a tightly welded tuff from one good insulators, if the pores or spaces are connected, the source may excel a very light tuff from another source.

30 Green tuff deposit in Eagle Tail Mountains. Note beds cut by dark volcanics. must be increased by closer evaluation of deposits granite-porphyry, diorite, gabbro, and some gneis- and of quarry sites, in order to reduce waste in sic-textured rocks. These rocks are common in Ari- slabbing and trimming. zona, but are confined essentially to the southern, southwestern and western parts of the state. Many of GRANITE the mountains in these parts of the state are composed of granite type rocks of various geologic By a casual glance at the geologic map of Ari- ages. Because of market conditions and past access zona, one may see that the state contains an un- and transportation problems, most of them have not limited supply of granite as a rock type. Of course, been prospected for possible granite quarries. not all of this rock is suitable for building stone, but For purposes here, only a few granite deposits out of the wide areas and many varieties, doubtless are mentioned. Near Cochise Stronghold in Cochise numerous excellent sources could be developed. For County, a very good, even and fairly coarse-grained many years, granite has been used as a building stone gray granite (granodiorite) can be quarried in large and for monuments within Arizona, but out-of-state blocks. In Greenlee County, north of Morenci, large markets have not been developed. Probably the reserves of a coarse-grained granite with aplitic largest use has been for public buildings, such as the veins and zones are available. This granite has an Yavapai County Court House in Prescott, and parts of over-all wine pink color due to dark red feldspars. the state capitol in Phoenix. Small amounts have been quarried from large Specifically, granite refers to a very particular residual boulders. A similar deposit of smaller rock type, but practically, the term applies to all reserves is near Clifton. Part of the state capitol related13 18 or "granite type" rocks, including building was built of granite from north of

31 Salome, in Yuma County. A "black" granite (gran- include careful evaluation of jointing, fracturing, odiorite?) is reported 6 northeast of Helvetia, Pima cleavage, and other lines or zones of weakness. Wide County. In Yavapai County, inexhaustible supplies of areas of some Arizona granites contain closely- a dark gray to white granite (quartz diorite) are spaced joints that were formed during cooling of the available, particularly in the Prescott region. In magma. These may preclude quarrying of large saw Maricopa County, abundant reserves of gray, white, blocks. Other areas may be massive, but contain and pink granite may be found; notable are the faults and fracture zones that must be avoided in mountainous areas in the northeast part of the county, quarrying. Also, most even-textured granites have and also south of Phoenix where a gneissoid granite more or less subtle cleavage, or directions along was quarried for part of the state capitol. Similarly, which the stone may break more easily; quarrymen Mohave, Yuma, Pinal, and Santa Cruz counties know this as "grain" and "rift". Fortunately, granite is contain large areas of massive granite. abundant enough in Arizona that problems of firmness and strength may be met by relatively little Granite and related rocks have certain well- and inexpensive exploration. known good characteristics for building stone. They are particularly strong and durable, and have low SLATE porosity; they are available in sleek homogenous textures, or in veined and patterned textures with Good slate in the classic sense is the least abun- swirls and irregular zones of fine-grained to coarse- dant of the major building stone types in Arizona. grained matrices. The stone takes and keeps a high Most slate used as building stone is a hard, durable, polish that brings out colors. On the other hand, it is finely-crystalline, metamorphic rock with strong a hard and dense stone, more difficult to quarry and cleavage in one plane.14 It is commonly blue-black, cut than others. known as `slate colored,' but also occurs in shades of In prospecting, assuming an available rock gray, red, green, and purple. The metamorphism that satisfies needs of appearance such as texture and has created slate from clay and shale beds is low- color, probably the most important quality to be grade; more intense metamorphism creates phyllite determined for granite is strength in large blocks. and schist. Thus, in Arizona it is not generally as First, it should be noted that in arid climates such as common a rock type as schist. in Arizona, granite characteristically erodes by The largest use of slate 24 has been for roofing disintegration. That is, being a crystalline rock com- plates, but many other products utilize its unique posed essentially of the three minerals, quartz, feld- character, such as blackboards, electric panels, bil- spar, and mica, all having different coefficients of liard tables and laboratory and other table tops. As a expansion, changes in temperature open cracks and building stone it is also used structurally for cleavage planes. Moisture penetrates; alternating wainscoting, sills, mantels, steps, etc., and is cur- cold and extreme heat over geologic ages cause the " rently a popular material for flooring. fresh" rock to break down, or "weather" to sharp, angular fragments. This resultant material is locally Most occurrences of slate in Arizona are more called "disintegrated granite," and incidentally has properly phyllite, and some are known as `mica slate.' considerable use in landscaping and other ground However, southwest of Walker, in the Bradshaw coatings. In places, outcrops of granite are weak and mountains of Yavapai County, deposits of excellent punky, being in the process of disintegration to slate are reported. It occurs in shades of green, depths of more than 10 feet. It is most important to brown, and black, and is hard and smooth, with good realize that a surface of weathered granite may cleavage. Development is said to be under way to conceal an entirely different looking fresh rock at remove sheets for cutting. depth, and may mask an excellent de-posit of building stone. Near Sunnyslope, north of Phoenix in Maricopa County, a deposit of largely blue-black and green Further, prospecting for firm granite should colored slate has been worked for a number

32 of years. It tends to be micaceous, and is hard stone, it has been used locally in the past; no and firm. It can be split into fairly large sheets. post-war production is reported. No production of cut or dimension slate is Limestone is a sedimentary rock composed reported from this deposit, but it is highly essentially of calcium carbonate, or when prized for rough, masonry walls. dolomitic, it includes magnesium carbonate. It is characteristically dense, compact, Also, in the Sierra Ancha District north of microcrystalline, and white in pure form. When Globe, Gila County, a hard, banded "ribbon it has been metamorphosed and recrystallized slate" is reported. It is said to be banded in dark to the point of taking a polish, it is called shades of red, gray, and purple. marble. Normally, limestone has been de- Doubtless other deposits of slate are available posited over wide areas." Thus, the Kaibab in Arizona. Systematic prospecting in areas of lime-stone (Permian) and the Redwall metamorphic rocks should bring to light much limestone (Mississippian) crop out in many good material for building stone. The places on the sedimentary plateau of northern Precambrian rocks of the mountainous Arizona. In the south-ern part of the state, southerly and westerly portions of the state several other Paleozoic and Precambrian units, hold the best possibilities. such as the Modoc, Escabrosa, Martin, Abrigo, LIMESTONE and Mescal limestones are present; these are Limestone, including dolomite, is common marmarized in places. In addition, lime-stone in Arizona, but in recent years it has seldom and limey or calcerous beds suitable for build- been utilized for building stone. As with other ing stone are included in other formations that types of are dominantly shale or sandstone, as for example,

Saw block quarry in light gray tuff.

33 limestone lenses in the Navajo sandstone.16 are pried loose and loaded for shipment. Due also to the cleavage, many surfaces are weathered to Clearly, limestone is abundant in Arizona, attractive colors, even at considerable depths. The needing market demand and systematic prospect- material is hard, but may be shaped by masons ing to provide suitable production areas. The ad- without extraordinary difficulty. The slabby shape vantageous potential quarry operation methods in of most stone also makes it adaptable to palleting Arizona merit attention here. In many parts of the for shipment. United States, suitable building stone deposits are on nearly flat land, or in topography requiring ex- Currently, the material having the so-called pensive vertical lift of stone from quarries. But in desert colors, shades of red, yellow, and brown are Arizona, many good deposits are located on hill- popular. Several small operations are being devel- sides, or in such topographic positions that quarry- oped in the Tucson area, but the largest production ing to great depths below surrounding surfaces need is in the vicinity of Phoenix. One of the oldest not be anticipated. Particularly notable are such quarries is in Sunnyslope, north of Phoenix. High- formations as the Kaibab limestone, which may be ly colored schist is quarried north of New River in found in thick, massive beds capping mesas. Under northern Maricopa County, and near Mayer in such conditions, large volume removal of stone Yavapai County. Also, extensive deposits have may progress horizontally rather than vertically, been developed elsewhere in the Bradshaw Moun- and in many cases, flow of materials from source tains, south of Prescott, and in the vicinity of Tuc- to loading for shipment may be entirely by son. gravity. MISCELLANEOUS STONE SCHIST Arizona has deposits of a number of rock types Schist is a rock type that is not traditionally that have been used for building and related pur- considered to be a common building stone, prob- poses, but because of lack of data, or specific po- ably because it does not readily lend itself to pre- tential in the building industry, they are classified cise cutting or shaping. Nevertheless, since World here as miscellaneous stone. This does not mean War II, thousands of tons have been produced in that any one of them is unimportant, or indeed, Arizona, and out-of-state shipments are becoming may not become a strong factor in the stone indus- a significant factor. Apparently, the variety of both try. A change in production techniques or con- subtle and brilliant colors available has made this sumer desire or knowledge of deposits, as in the stone a popular wall facing. case of schist, could warrant detailed study in the Arizona is peculiarly endowed with large sup- future. Generally, their production has been erratic plies of schist. Although young (Mesozoic) schist and small due to their rarity, types of deposit, diffi- is reported, as in Yuma County, most of it occurs culty of being worked or lack of markets. Togeth- in the oldest of rocks, Precambrian in age. Rocks er, however, they comprise a group that adds to the of this age, particularly common in southern and necessary variety of available stone, and thereby western Arizona,ll are only scantily available or increases the potential of the industry as a whole. even absent in many other states. Modern architec- Rhyolite and porphyry tural trends requiring color and textural relief to Grouped here are all of the light-colored vol- otherwise monolithic structures have brought nu- canic rocks including dacite, rhyolite porphyry, merous, small quarries of schist into operation. and tuffaceous rhyolite, that are abundant Production methods are simple. This meta- throughout the state, excepting, of course, tuffs as morphic rock generally cleaves into irregular, platy previously described. Being volcanic in origin, pieces, due to the common orientation of platy they are either characteristic or related to the many minerals, largely mica. After overburden is re- Tertiary and Cretaceous rock areas in the state, and moved, firm rock is exposed by light blasting, and gradations pieces that may be handled by one or two men

34 between them are common. As a whole, they oxide) to affect the rock along the planes of lack the light weight and cuttability of tuff, the fracture, and more or less into the rock, cleavability of sandstone and slate or the probably along flow lines. When quarried, the ability to take polish as granite and marble. rock tends to have colored bands parallel to Nevertheless, the variety of colors and fractures. Interesting and attractive patterns textures, and the relative abundance give them and "designs" may also be ex-posed by cutting a strong potential as building stone. Perhaps the such rock. availability of tuff has caused them to be Of particular current interest are the many overlooked. surface deposits of both residual and In Greenlee County near San Carlos, a transported boulders of rhyolite porphyry. tuffaceous rhyolite has been quarried. It is Weathering has created shades of red, brown, fairly massive, reddish in color, and in places pink and even lavender that make the rock it has attractive banding of reddish and light desirable in masonry walls and landscaping. colors such as cream. Northeast of Wickenburg, Large areas near urban centers in Arizona Maricopa County, a rhyolite with bands and have been cleared of this surface material; halos of red to brown is reported. It is fine- shipment out-of-state is also reported. grained and can be cut to good building stone. Basalt and scoria Another deposit west of Alamos Springs in In parts of the United States, this heavy, Yuma County is prized for the halo bands of dense, very hard, fine-grained, and generally salmon-pink to red in a light gray back-ground. dark-colored rock is a major type of building Regarding halo bands, in places some fine- stone. Vast areas of basalt are present in grained rhyolites have a fairly regular jointing Arizona.il Although is has had local use, no and fracture system, allowing alteration ( significant shipments are reported. It is

Outcrops of massive granite. granite," 7 and includes other basic rocks such as is in building materials, such as wall facings, sills, diabase and diorite. In Arizona, it is commonly table tops, trims, floor tiles, and moldings. The called "malpais". relative ease of cutting and polishing may make it Because of the weight, hardness, and subdued competitive with other textured, polished stones, in and somewhat somber colors, basalt has a limited spite of the quarrying difficulties. potential as a dimension-cut building stone. How- In Santa Cruz County, northwest of Sonoita, a ever, currently the weathered basalt is popular for type of onyx is variously reported as onyx marble masonry walls, wallfacing, and landscaping rock. In and travertine.6 It was found in a cavern in some cases, the rounded boulders transported by limestone on the east side of the Santa Rita Moun- erosion are desired, and in other cases, the tains. It is reported to be various shades of brown, weathered but more angular pieces near the out- and to be sufficiently massive and firm to be re- crops are used. moved in large blocks. Somewhat more difficult to obtain are the Near Cave Creek in Maricopa County, green- scoriaceous basalts, or scoria. This material is some- ish and yellowish onyx with veins of brown and red what lighter in weight because it contains vesicules is deposited in intimate association with basalt. or holes due to contained gases in the original lava. Although of fine quality, only relatively small pieces The vesicules are often not connected, and may be may be removed due to shattering by volcanics. filled with white, secondary minerals. The more representative scoria resembles clinker or slag, and Near Mayer, Yavapai County, considerable 26 is commonly red or maroon in color. Irregular dep- onyx has been produced. It is white and pale green osition of scoria makes quality control difficult, but in places, but the deposit contains much amber, at this time large tonnages are being sought to meet brown, and yellow stone. Several openings have an increasing demand. been made in a deposit that covers about one quarter of a square mile. In one place, a large open pit, Travertine, tufa, and onyx marble approximately 40 feet across, has been excavated, exposing onyx on three sides; beds here vary from These stones of ancient reputation occur an inch to more than 10 feet thick, and are reported sparsely in Arizona. They all originate from the to be more than 20 feet thick elsewhere. The beds same process of calcium carbonate precipitation in are also wavy and irregular. Adits have been dug springs, streams, or caves. Sometimes beds are only more than 10 feet into the vertical walls of the pit. a few inches thick, but may be scores of feet thick. Excellent deposits of multi-colored onyx are Travertine is a solid, layered rock, which when pure located approximately 20 miles north of Globe, Gila is white, but may be colored to many hues due to County. 300,000 to 1/2 million tons of gross contaminating elements such as iron oxide or material are estimated to be available with a sub- organic material. Tufa is cellular in structure, and stantial portion useable or recoverable. As many as onyx marble is banded and crystalline. All may 17 different colors of banded, crenulated, and contain some siliceous material, and in fact, true veined material are reported. In places, the bands onyx is a variety of agate, primarily silica. Being and crenulations are fine and tight. Elsewhere, made dominantly of calcite, they are soft, cut easily, massive white and ivory colored onyx with fine may be carved, and may take a high polish. veins is present. Production consists largely of in- Onyx marble, or decorative onyx is probably termittent, surface work over the past two years. It the most spectacular of the three stones, and even is believed that consistent colors and patterns can though deposits of travertine 6 and tufa a are present be quarried in large saw blocks; the stone contains in the state, onyx presently exceeds the others in some vugs that appear firm. What work has been demand. Due to the irregular deposition of onyx, done indicates relatively little fracturing in the rock quarrying of large volumes of consistent quality is and one bed is 20 feet thick over a con- difficult. The market for novelties made of onyx is well established, but the stone's greatest potential

36 siderable distance. Also, the stone contains some known in Arizona," and this rock type is also found siliceous material, agate or chalcedony, largely as members in other formations, such as associated filling vugs. Due to the presence of the harder, with marble. Production of quartzite has been siliceous material, and particularly for volume pro- meager, but the many deposits in Arizona should duction, diamond saws are indicated for cutting. get attention in the future. Quartzite and Quartz Quartz, on the other hand, has been a common A sandstone made of quartz grains, that has building stone for many years. As a stone, the term been metamorphosed to the extent that the rock will quartz usually refers to vein deposits, where it is break through the individual grains, is termed often found in shades of white or milky white. Rose quartzite. Impurities in the original sandstone, or quartz is rarer, and currently much in demand. introduced by metamorphism can give quartzite Commercial deposits are mostly at least several almost any color and banded effect. The rock is hard feet wide, and may compose small hills, making and tough, and many varieties will take a good extraction easier. Quartz has a hardness and polish. Quartzite cuts and polishes with about the toughness equal to quartzite, and characteristically same ease as granite. In places such as the northeast breaks with a glassy, conchoidal fracture. corner of Pima County, some quartzite cleaves along Numerous deposits of quartz have been bedding planes, yielding sheets, plates. and blocky worked for flux in copper smelting, and these and pieces, depending on the thickness of the beds. others can be used to provide building stone. Not- Many beds are massive and several feet thick, and able deposits of rose quartz are northeast of Cave could be quarried for saw blocks. Creek in Maricopa County, in the Cerbat Moun- At least six quartzite formations are well- tains, near Chloride, Mohave County, and north

Schist wall (lower portion) with top of exposed quartz aggregate.

37 of Bagdad in Yavapai County. Although deposits of Magnesite white quartz are generally not large in size, they are North of Phoenix near Rock Springs in Mari- common in all counties except Apache, Navajo, and copa and Yavapai Counties, deposits of a white and Coconino. cream-colored rock called "magnesite" may be Jasper found. It occurs over a fairly large area as beds at Jasper is a hard, dense, variety of silica re- least ten, and possibly many more feet thick. It sembling chert in some respects. It is opaque, and appears to be opalized carbonates of calcium and occurs in colors of black, brown, and yellow, but magnesium. Surface material varies from hard and most commonly red; it takes a high polish. Being a firm to crumbly. Recent production has increased siliceous precipitate from cold water, it occurs in markedly. large and small irregularly-shaped masses, and Serpentine sometimes in fairly widespread `beds'. Although the A "serpentine" stone in shades of pink, gray, hardness and irregular deposition do not give it the and purple has been reported from southwest of large volume potential of some other stones, jasper is Globe, Gila County. The rock is said to be banded considered unique and is in demand for special uses. and fairly hard, and is being produced for shipment. Jasper may be found in every county of Ari- V AVAILABLE STONE — LAND STATUS AND zona, but the best known deposits are in a wide area ACQUISITION OF MINING RIGHTS where Yavapai, Gila, and Maricopa Counties meet, between Cave Creek and Sunflower, and north along In the future, doubtless many new sources of the Mazatzal Mountains. Here, red, green, and purple stone will be developed in Arizona. The state con- jasper, partly banded and crenulated is exposed in tains vast areas that are available for prospecting, many places; some of it is associated with mercury ( but due to the several basic kinds of land owner- quicksilver) deposits. Fairly extensive and thick beds ship, mining rights must be acquired in several west of Sunflower have been worked. Also, deposits different manners. For purposes of developing stone in northwest Yavapai County and Mohave County are quarries, four types of land according to basic own- reportedly being opened. Out-of-state shipments of ership may be considered; 1) private land, 2) U. S, rough, quarry run stone from various parts of the public domain open to mineral location, 3) Arizona state are re-ported. state land, and 4) Indian land. These types of land Copper-stained stone constitute 90 percent of the state; the other 10 percent consists of Federal lands withdrawn for Currently, any rock type containing substantial military purposes, parks, reclamation projects, and quantities, coatings, or stain of the blue and green, other uses not open to mining. The approximate secondary or oxide minerals is in demand. The acreage and proportions of these lands are as fol- extensive copper mineralization in Arizona provides lows: ample supplies, not only in outcrops, but in many mine dumps. The brilliantly colored secondary minerals, chiefly chrysacolla and malachite,' are difficult ores of copper to process, and are often discarded or stockpiled at mines for later use. Where the rock is firm, its value as building stone exceeds Type of Land its value as ore. Numerous buildings in Arizona have Ownership Approximate Acreage Percent wall facings of oxide copper stone, and substantial Private 10,200,023 14 shipments to other states attest the growing U.S. Public Domain 24,451,252 34 desirability of this unique stone. State of Arizona 10,785,564 15 Indian 19,378,795 27 Other 7,872,366 10

Totals 72,688,000 100% Private land Inasmuch as all of Arizona was once Federal land, private ownership has been acquired through

38 patents of one kind or another, such as homestead, dure are greater than that for disposal of common mineral, and land grant patents, and the land is now varieties by contract. Materials which have a dis- owned in fee simple. Therefore, private land is also tinct and special value are not considered "common known as patented or fee land. varieties." It appears that such characteristics as Acquisition of mineral rights on private land in unique coloration, ability to cleave or be split easily Arizona is the same as any other place. Some-times into slabs or sheets, or ability to be cut to dimension land is bought outright, but more commonly lease could cause a particular deposit of stone to be arrangements are negotiated with owners. Some classified as uncomomn. Stone having no unique owners want a flat rental, others want a royalty on chemical or physical properties would normally be material removed or a combination of both. a common variety. There must be a market for the Prospecting should be done with the consent of material at the time of location to make it valuable owners. and subject to location. However, the law is so new that few guide lines have been established, and U. S. Public Domain each deposit must be evaluated by itself. It may be inferred that today's market requirements of high These lands are known as Federal, or simply " specifications and unique appearance of products U.S." lands. They consist largely of U. S. Forest should presume the existence of many uncommon lands, and of unappropriated Federal lands man- varieties of stone that would be locatable as mining aged by the U. S. Bureau of Land Management. claims. Mineral rights for unique varieties of stone may be acquired on open public domain, under the State of Arizona Land mineral location laws applicable to lands in sixteen western states. Prospecting may be done without State land is also subject to entry for mining permit. Upon discovery of a valuable deposit, purposes; prospecting may be done without a per- claims which are generally 600 x 1500 feet in size, mit. Upon discovery of a valuable mineral deposit, a are located, location notices are filed, and mining claim may be located in essentially the same man- or quarrying may begin. Claim monuments and ner as on Federal land, or according to 20-acre discovery work must be done according to General claims set out by legal subdivision. Stone is included Mining Regulations. One may locate and mine on with other minerals, without distinction as to com- as many claims as necessary, and upon which a dis- mon or uncommon varieties. covery is made; neither a lease nor royalty pay- The major differences between mining on State ments are required. Under certain conditions, min- and on Federal land are that after location on state eral claims may be patented; that is, full rights to land, a 20-year lease is obtained, royalty on the land are granted the claim holders. production is paid, and no patent proceedings are Under an Act of July 23, 1955, the U. S. min- available; also, lessees pay an annual rental of $15. ing laws were amended to provide for multiple use 00 per claim. and hai, a preferred right to renewal of land, restricting miner's use of the surface of of the lease on expiration. Leases may be assigned unpatented claims to those activities necessary to or transferred, wholly or in parts. prospecting, exploration and mining. Also, "com- State lands are managed by the Arizona State mon varieties" of sand, stone, gravel, pumice, pum- icite or cinders were made non-locatable, and are Land Department. Proof of discovery is required, subject to disposal by sale under contract. Thus, a and for stone claims this may consist of sending a common variety of stone could be removed only sample to the Department, along with an affidavit under contract, and by payment of a unit price for that the sample came from a particular claim. Roy- the stone removed. alty is payable at the rate of 5 percent of the net The question of definition of "common varie- value, after deduction of cost of processing, costs of ties" is, of course, important to the stone industry, transportation, and applicable taxes. Rules and because rights under mineral claim location proce regulations, and instructions on procedure to obtain a mineral lease are also available. Arizona industry would be complete without a realistic eval- encourages mining on its land as well as throughout uation of transportation conditions. Length of haul, the State, and a substantial amount of the present modes of transportation, availability of loading fa- stone industry obtains raw materials from State land. cilities, and freight rates loom large in the determi- nation of whether or not a particular stone can Indian Land compete with other materials. This is particularly true Approximately 27 per cent of Arizona is Indian in Arizona, where the appeal of west coast markets is land, divided into separate Indian Reservations strong. Not only must Arizona stone compete with scattered over the state. Generally, exploration and manufactured materials, such as glass and aluminum, mining rights may be acquired by negotiation. with but it must be competitive with stone from other individual tribes, under the supervision of the U. S. states; Arizona has an obvious advantage over Bureau of Indian Affairs. Most commonly, leases eastern stone moved by truck and rail, but may not be are obtained for a particular area, and payment so fortunate regarding overseas haul, even from includes a fixed rental, plus royalty. Where possible, foreign countries. The importance of transportation to the use of Indian labor is encouraged. the stone industry may be seen by the general Surface and subsurface location of quarries near major transportation routes. Some quarry operators rely in part on their own trucking facilities; others contract hauls, and use both truck and railroad transport. Between truck and In addition to the above general ownership of railroad service, each has advantages that must be lands in Arizona, attention should be called to the weighed for operation of any given stone deposit. variations in surface and subsurface ownership. That The transportation of goods is a more complicated is, title to the surface may be held by one of the U. S. field than many producers in all industrial fields Government, State of Arizona, private parties, or realize. Specialist representatives of common carriers Indians, while title to the subsurface or mineral rights in Arizona stand ready to analyze, and to may be held by another of those four. For example, recommend proper arrangements and adjustments to the surface rights may be owned by the State, while meet the conditions of new and changing industries. the subsurface is held by the Federal Government; in Their aid should be sought. Common carriers must this case, mineral claims could be located according quote rates on any and all commodities except a few to Federal procedure. Or, private parties may own specialties of "extraordinary value." They are the surface, but the State owns the mineral rights or constantly evaluating rate schedules to make them subsurface, making it subject to State mineral leases. appropriate for a given volume of movement. Rates Most commonly, the State or private parties own are generally first established for a particular need. surface rights, with subsurface reserved to the Such rates may be applied to other similar needs even Federal Government. though they may not be wholly applicable, unless In any case, this divided land ownership, which circumstances for additional and different rates are could be called "vertical ownership," is a factor to be presented by shippers. Thus, more flexibility is considered in exploring for stone quarry sites. available, particularly for new commodities or Although seemingly complicated, its total effect has forms. been to reserve large areas for mineral claim location Several general principles of common carrier under Federal or State laws. The U. S. Bureau of transportation are pertinent. Shippers should de- Land Management and the Arizona State Land termine the difference between "class" and "com- Department make both records and help available to modity" rates. The former are more general, and determine land status. apply to all of one type of carrier, and the latter are more detailed, for specific volumes and haul routes. VI TRANSPORTATION AND Secondly, interstate and intrastate haul conditions FREIGHT RATES

No consideration of the economics of the stone

40 may be different, affecting rates and franchises. moved by rail at the following representative rates : Thirdly, minimum weight requirements must be considered. For example, present truck and rail-road CURRENT CARLOAD COMMODITY RATES rates for hauling stone from Ashfork to the Los FOR RAILROAD SHIPMENT Angeles area overlap according to the various Natural stone, rough quarried, or broken minimum weight requirements. Another important (no packaging required) factor regarding rates is the degree of finish of a FROM: Northern Arizona, viz: Ashfork, Drake, product. Fundamentally, carrier's rates are based 1) Prescott, Seligman the work done in hauling, 2) the particular risks Rate per Minimum TO: encountered in handling and hauling goods, and 3) ` 100 lbs. lbs. Los Angeles, California 60,000 the wear-and-tear' and damage done to transport $0.455 .335 80.000 equipment. It may be seen that in general the higher San Francisco, California .445 100,000 value goods require higher rates, and many different Fresno, California .415 100,000 classifications are created. With stone, as with many Seattle, Washington .88 100,000 other products, the more finished the material, the 1.21 50.000 higher is its value. Related to this, stone producers Portland, Oregon .88 100,000 are becoming more interested in packaging, not 1.21 50,000 Chicago, Illinois .93 80,000 only for ease of handling, such as cut stone steel- Kansas City, Missouri .84 80,000 taped on pallets, but for protection of products, and Milwaukee, Wisconsin .93 80,000 for merchandising of building kits. For some Houston, Texas .75 80,000 products, carriers rates vary according to packaging. Railroads Other features related to rail transportation that should be considered are loading sites and Two major rail systems serve Arizona; the processing sites. Most stations have public loading Southern Pacific Company in the southern part of tracks (team tracks) and also have some leasable the state, and The Atchison, Topeka, and Santa Fe Railway Co. in the northern part of the state. Both industrial sites on trackage (industry track). All have had limited experience in hauling stone in named stations have sidings, and these are more Arizona, and consequently do not have detailed numerous than commonly believed. Moreover, be- commodity rate schedules for many potential ship- tween stations railroad companies have rights of ping points. Below is a general classification of way of an average of about 100 feet on both sides stone for rail haul, according to degree of finishing: of tracks, which under certain conditions may be 1. Rough quarried, or broken stone. used for additional facilities. Thus, if volume of 2. Finished not more than sawed, dressed, or haul warrants, processing plants may be located cut to shape. adjacent to rail loading facilities. 3. Polished, decorated, finished. Trucking

Within the above groupings, there are, of A number of substantial interstate and intra- course, many possible stone commodities. Move- state motor carriers serve Arizona. They, as well as ment of stone in the southern part of Arizona has the railroads, are eager to expand services, and help been erratic over many years, so quoted rates may be unrealistic for specific commodities, but in the develop new industries in Arizona. Hence such northern part of the state, stone is now being services as new accounting methods to save paper work by shippers, and arrangements to spot trailers for loading at shipper's convenience are offered. Some independent carriers haul stone under ne- gotiated contract, but common carriers haul ac- cording to established class or commodity rates. Below is a sample of present truck rates for stone

41 shipped to the Los Angeles, California, area: desiring to relocate if employment could be pro- vided. Therefore, any shortage of properly trained and experienced personnel for the stone industry CURRENT COMMODITY RATES FOR should be only temporary. TRUCK SHIPMENT* The ultimate personnel needs of an expanded COMMODITY: viz: flagstone, gravel, gypsum stone industry fall into three categories. First, effi- rock, lime rock. ciency in production can undoubtedly be in-creased TO: Los Angeles, California, area by skilled quarryman. Even though each rock type Min. Per Per Ton has its own peculiar characteristics to be learned and FROM: Rate Wt. Ton Miles Mile mastered, competent stone workers from one part of Kingman $.51 20,000 $10.20 381 $0.0267 the country can readily adapt themselves to a new Seligman .51 20,000 10.20 414 .0246 Ashfork .51 20,000 10.20 425 .0240 type of rock. Second, an expanded stone industry .43 30,000 8.60 425 .0202 would presume closely associated milling and Williams .60 20,000 12.00 445 .0269 processing, requiring skilled operators of wire saws .50 30,000 10.00 445 .0224 and diamond and other rigid saws, and of grinding Flagstaff .68 20,000 13.60 465 .0292 and polishing equipment. Third, much of the present .65 30,000 13.60 465 .0279 quarry and processing practice requires workers Prescott .43 30,000 8.60 372 .0231 qualified to operate light and heavy machinery. A Phoenix** .41 20,000 8.00 392 .0204 more integrated, mechanized industry would add VII LABOR MARKET further to these requirements. Arizona's large mining industry could doubt-less Even a modest growth. of the stone industry in provide many qualified workers for the above Arizona implies a need for skilled and semi-skilled projected needs. Many people in the present stone labor. The number presently employed in this field is industry have mastered the intricacies of particular not only not known, but is difficult to determine, rock types. Further personnel needs can be solved because of the many small operations being carried through the national clearance program of labor on at irregular intervals. From a general knowledge placement. of the production of stone during 1960, it appears that approximately 200 persons consider the major VIII DEPLETION ALLOWANCE, TAXES, portion of their living as being made in stone AND INSURANCE production. At least that many again derive some of their income from stone production, including the Contrary to popular opinion, tax depletion part-time prospector who sells an occasional load, allowances are not limited to oil and gas production. and the seasonal worker in established quarries. Dimension and ornamental stone, and stone for Many others have some knowledge of stone through aggregate, and road materials are all included in its distribution, sale, and use in construction. Of all depletion allowance schedules as well as uranium, of these, few are considered skilled stone workers. copper, and other minerals. In order to keep pro- The industry is new in Arizona, and many of those ducers of irreplaceable natural resources on an even who are skilled became so through experience over tax basis with manufacturers whose need for de- the last few years. preciation (depletion) allowances for capital re- In addition to what is considered to be a plen- placement is obvious, Congress has provided that a tiful general labor market, Arizona's unique climate certain portion of gross income from a mining or is often used to attract specialists in many fields. The quarrying operation may be deducted before Arizona State Employment Service of the calculating taxes. In most industries, the cost of the Employment Security Commission can readily obtain capital investment being depleted is known, or can be qualified workers in any field, through the highly evaluated, and a depreciation schedule can be set up efficient nationwide clearance program; they report for its replacement. But in mining or quarry- that 30,000 inquiries annually are received from out- of-state skilled and semi-skilled workers

* Rates as of 2-10-61, shown in Interstate Freight Carriers Conference, Inc., Local and Joint Freight Tariff No. 1-E, MFICC No. 7, first revised page 311, items 5620 & 5630. ** Commodity: viz: Building stone, NOI, flagstone, gypsum rock, lime rock.

42 ing, the reserves of ore or stone are the capital be- tions and bearing walls, are more efficiently met ing depleted; this capital is difficult to evaluate and by other materials. Also, when rapid construction to schedule replacement or eventual loss, so the is urgent and essential, such as after World War somewhat arbitrary basis of a percentage of gross II, the durability, low maintenance and beauty of income is used. That is, it is asumed that if a stone may be sacrificed temporarily. certain portion of gross income from a property is However, excepting these two circumstances, not taxed, the money saved will eventually equal several factors should combine to create a the value of the deposit. rennaissance in the stone industry. First, of Thus, the following depletion allowances course, the tremendous volume of construction in apply in the stone industry: the United States has made part of the use of new materials additional rather than replacement. Dimension and ornamental stone ...... 15%* Stone is being made to compete in cost with Common varieties of stone—including those other materials by standardizing sizes and sold for concrete aggregate, ballast, shapes, and by volume and integrated production. road material, riprap, rubble, or similar Also, architects and designers are abandoning purposes ------5 rigid concepts of stone use, making stone fit Inevitably, taxes are an important considera- designs rather than designing to fit stone. tion in any business. Historically, Arizona has been Moreover, the very use of new materials sympathetic to mining industries, and today con- mentioned above, contrives in two ways to tinues to encourage development of its resources. promote use of stone; one, by creating a need for Taxes facing the stone industry are not excessive. textural and color relief from the coldness of The most notable assessment is the state-wide sales manufactured materials, and two, by providing tax, as follows: structural members to support stone work in circumstances other-wise unfeasible. Wholesale sales tax ...... 1 %2 Jo Therefore, one may look with optimism to- Retail sales tax ------3% ward a steady growth of the stone industry, roughly parallel to normal construction needs. In addition, attention should be drawn to the Assuming the post-war building gap to be requirement for State Industrial Insurance. This essentially closed, construction needs should in insurance is paid on employees, and the amount turn be parallel to population growth. If, then, the varies according to the job, or type of work, and to potential of Arizona's stone industry may be the experience record within an industry.** linked with population growth, the state is indeed IX POTENTIAL fortunate. Within the optimum transportation zone, the Pacific South-west, population trends are awesomely upward. Projections show 3 that Arizona stone has the potential of being a by 1970, five states bordering Arizona ( well-known, highly desired, and industrially im- Colorado excluded) will comprise a 25,000,000 portant construction material. In order to realize market. the full potential, people in the stone industry must recognize the use-position stone is in, relative to Considering the present status of the stone other materials. Then the resources in Arizona, and industry in Arizona, one may first conclude not the status of the state's present industry must be only that the variety of raw material is wide, and evaluated. An expanded and stable stone industry that many unique stones are available, but also will develop, if modern production and marketing that the reserves are more than ample in most methods are diligently applied. cases, and almost unlimited in others. Second, one should freely conclude that as an industry, stone Although concrete block, steel, aluminum, and production in Arizona is in its infancy. Only since glass have replaced stone in some uses, this should World War II, have population and construction not be looked upon as a crippling blow to the stone growth warranted much more production than industry. True, heavy structural needs, i.e., founda- would fill local needs.

* Not to exceed 50% of net income computed without allowance for depletion.

** Further general information regarding taxes is avail- able from the Arizona Development Board and detailed data are, of course, available from the Arizona State Tax Commission, 43 How, then, may this burgeoning industry with zona is the quarry wire saw. Consisting essentially ample raw materials realize the indicated of a continuous, twisted wire cable run through potential? On the basis of study of stone pulleys, the saw cuts a groove by carrying abrasive production problems, mention of some of the materials across the stone. Various devices keep means has been made previously in this text. A the wire taut, and the groove clean and straight. more formal listing of general needs follows. Long cuts may be made, and once a cut is started. little attention is required. Also, as permanent 1. Volume markets and production quarry sites are established, producers may look In today's cyclical economy, stability in most to more permanent stone loading and handling industries is achieved only with large and diversi- equipment for processing in quarries. fied markets that are fed by volume production. 3. Integrated industry Certainly, to be important in the vast construction Sandstone is now quarried, hauled, processed, industry, Arizona stone must be produced in quan- and marketed by some operators. Other standstone tities able to meet needs that arise or that may be producers and nearly all other operators perform developed. The products may excel in beauty and only one or two functions. For sufficient profits, durability, but they must also be competitive in and to remain stable and competitive, it is prob- quality, adapatability to construction methods, and able that all dimension stone producers, and cer- in cost. To some extent, volume demand will in- tainly producers of stone to be polished must an- crease without stimulation, but it can be hastened ticipate performing all functions from quarry to by concerted effort on the part of Arizona stone final sales. producers. Advertising and promotion are Capital necessary phases of any marketing.* The potential Without doubt, investment capital is to business interests and to the State as a whole necessary to implement all other general needs. justifies increased effort in market creation. With Some operators maintain that capital is all that is notable exceptions, producers have concerned needed, but the records show that investment themselves largely with production problems and capital by itself will not necessarily produce the quality control. The need for a state-wide trade stability that combined volume markets and association should be considered, state agencies production, mechanization and integration can should be given data by which they can publicize produce. the industry, and individual producers must plan for larger sales and promotion programs. Research and exploration A combination of three rock types may lead the way toward volume markets. Sandstone, mar- The organizations and efforts made to create ble, and tuff all have the potential of meeting most volume markets, as well as individual producing market demands; all can be produced in large firms must contribute to research and exploration. quantities; all can be cut or split to standardized New techniques are needed in finding deposits, or dimensions without undue cost; all have a variety in determining the proper quarry sites in known of unique colors and textures. Sandstone is becom- deposits. Hardly a quarry in Arizona has reached ing well established, and marble is a traditionally depths sufficient to know the true nature of un- desirable polished stone. Tuff excels in light weathered or fresh rock. New quarrying techniques weight, insulation, and ease of cutting, along with and processing methods may be developed, and soft colors and textures. quarry and plant layouts to utilize favorable terrain 2. Mechanization are needed. Techniques may be devised for production of more than one type of stone in a If markets are increased. stone producers single processing plant; production of some of the must look to mechanization to achieve large less produced stone, such as rhyolite, quartzite, volume production with competitive costs. One of and onyx could possibly be dove-tailed into the most promising mechanical devices not yet production of sandstone, marble, or tuff. used in Ari- Also research is needed to meet and to help In this regard, the industry suffers somewhat from lack of precision in terminology. Architects, designers, and builders are humanly attracted to materials whose characteristics they can visualize and measure. This fault faces all new industries, and can be remedied by cooper- ation among producers and with users,

44 create new trends. Shapes and dimensions must aggregate, and may even be able to develop pre- conform to requirements of steel, concrete, glass fabricated masonry units; not only the cost of stone, and other materials. Stone producers must work but the time needed to handle it during construc- with producers of pre-cast slabs containing exposed tion must be competitive with other materials.

Colored marble being crushed, screened to size, and bagged for shipment.

45 X GLOSSARY

1. AGGREGATE — The mineral material, such as sand, gravel, shells, slag, or broken stone, or combinations thereof, with which cement or bituminous material is mixed to form a mortar or concrete.13 2. ASHLAR — Rectangular blocks having sawed, planed, or rock-faced surfaces, contrasted with cut blocks which are accurately sized and surface tooled,24 may be laid in courses. 3. BASALT — A fine-grained, extrusive (volcanic) rock, basic in composition, and generally dark-colored and hard. 4. BEDDING — Collective term signifying existence of beds or laminae in a rock; planes dividing sedimentary rocks of the same or different lithology.13 5. BROACH — To drill or cut out material left between closely spaced drill holes. Also, a mason's sharp pointed chisel for dressing stone. 6. CHANNELING MACHINE — A track-mounted machine operating steel bars in a chopping action that cuts narrow channels to remove blocks of stone.14 7. CROSS-BEDDING — The arrangement of laminations of strata transverse or oblique to the main planes of stratification.13 8. CURBING — Slabs and blocks of stone bordering streets, etc. 9. DACITE — A fine-grained, extrusive (volcanic) rock, intermediate in color and composition between basalt and rhyolite. 10. DOLOMITE — A sedimentary rock composed of carbonate of calcium and magnesium; resembles limestone. 11. EXPOSED AGGREGATE Phrase applied to the larger pieces of aggregate purposefully exposed for their color and texture in a cast slab or in concrete or paving. 12. FIELD STONE —Loose stone scattered by natural processes over the ground surface. 13. FINES — The powder, dust, silt-size, and sand-size material resulting from processing (usually crushing) rock. 14. FLAGSTONE — Thin slabs of stone used for flagging or paving walks, drive- ways, patios, etc. It is generally fine-grained sandstone, siltstone, or slate, but some limestone and thin slabs of other rocks may be used. 15. FREESTONE — A stone that may be cut freely in any direction without splitting. 16. GRAIN—The second easiest cleavage direction in a rock.? (Compare to rift.) Also, particles (crystals, sand grains, etc.) of a rock. 17. GRANITE — A fine to coarse-grained, igneous (plutonic) rock consisting of quartz, feldspar, and mica, with accessory minerals. Granite-type rocks include those of similar texture and origin. 18. IGNEOUS One of three great classes of rock, igneous, sedimentary, and metamorphic; solidified from molten state, as granite and lavas. 19. LAVA — A general term applied to igneous rocks such as basalt and rhyolite, that erupted from the earth by volcanic action. 20. LIMESTONE A common sedimentary rock composed of calcium carbonate; includes many varieties. 21. MALPAIS Literally, badlands refers to the dark-colored rock, commonly lava, in rough terrain. 22. MARBLE — A metamorphic rock composed essentally of calcite and/or dolo- mite, generally a recrystallized limestone. In the trade, it includes most calcare- ous rocks that will take a polish.13 18 23. MARMARIZED Refers to the process of recrystallization of limestone to marble.

46 24. METAMORPHISM — The change or alteration in a rock caused by exterior agencies, such as deep-seated heat and pressure, or intrusion of rock materials. 25. OBSIDIAN — A glassy phase of lava. 26. OPALIZED — The introduction into a rock of siliceous material in the form of opal, a hydrous silicate. 27. PHENOCRYST In igneous rocks, the relatively large and conspicuous crystals in a finer-grained matrix or ground-mass. 28. PORPHYRY — An igneous rock in which relatively large and conspicuous crystals (phenocrysts) are set in a matrix of finer crystals. 29. PUMICE — An exceptionally cellular, glassy lava, resembling a solid froth. 30. QUARTZITE — The metamorphic equivalent of a quartz sandstone, in which the grains have recrystallized or have grown together. 31. RIFT — The most pronounced or easiest (see grain) direction of splitting or cleavage of a rock. Rift and grain may be obscure, as in some granites, but are important in both quarrying and processing stone. 32. RHYOLITE A fine-grained extrusive (volcanic) rock, acidic in composition, and generally light-colored. 33. ROCK — A general term applying geologically to any naturally formed aggregate or mass of mineral matter, whether or not coherent, constituting an essential or appreciable part of the earth's crust; includes formations, and loose masses such as sand, gravel, or clay beds, as well as hard and solid masses such as granite or limestone; sometimes synonymous with stone (see below.) 34. RUBBLE — Rough, irregular pieces of broken rock.13 In the trade, it is some- times confused with ashlar; ruble may be partly trimmed or squared, or may be irregular, or both (rough squared.) 7 35. SANDSTONE — A consolidated sedimentary rock composed of sand grains. 36. SCALE — Thin lamina or paper-like sheets of rock, often loose, and interrupting an otherwise smooth surface on stone. 37. SCHIST — A loose term applying to foliated metamorphic rocks; generally medium or coarse-grained, with more or less parallel orientation of lamellar minerals such as mica, allowing it to split easier in one or two directions. 38. SCORIA — Irregular masses of lava resembling clinker or slag; may be cellular ( vesicular,) dark-colored, and heavy. 39. SLATE — A very fine-grained metamorphic rock derived from clayey sediments, and having excellent cleavage along one plane due to micaceous minerals. 40. SPLIT — Division of a rock by cleavage. 41. STONE — Sometimes synonymous with rock, but more properly applied to in- dividual blocks, masses, or fragments taken from their original formation or considered for commercial use. 42. STRATIFICATION A structure produced by deposition of sediments in beds or layers (strata), laminae, lenses, wedges, and other essentially tabular units.13 43. STRIP — Removal of overburden or waste material. Also, elongate or linear pieces of cut stone. 44. TERRAllO A type of concrete in which chips or pieces of stone, usually marble, are mixed with cement and are ground to a flat surface, exposing the chips which take a high polish. 45. TUFF — Cemented volcanic ash; many varieties included. 46. VUG — A cavity in rock; sometimes lined or filled with either amorphous or crystalline material; common in calcareous rocks such as marble or limestone. 47. WEDGING — Splitting of stone by driving wedges into planes of weakness. 48. WIRE SAWN — A method of cutting stone by passing a twisted, multi-strand wire over the stone, and immersing the wire in a slurry of abrasive material. XI ANNOTATED BIBLIOGRAPHY (Numbers in text refer to numbering below.)

1. "American Society of Testing Materials Standards." 1916 Race Street, Philadel- phia 3, Pennsylvania. A compendium of accepted testing procedure. Pages 1117-1139 are on natural building stone. 2. Bates, Robert L. "Geology of the Industrial Rocks and Minerals." Harper Brothers, New York, 1960. A scholarly, up-to-date source of general data. Pages 23-156 are on indus- trial rocks, and include building stone, their characteristics and occurence, Abundant bibliography. 3. "Bibliography For Industrial Arizona." Arizona Development Board, Phoenix, Arizona. Reference to industrial data, classified, sources given. 4. Bromfield, C. S. and Shride, A. F. "Mineral Resources of the San Carlos Indian Reservation, Arizona." U. S. Geol. Surv. Bulletin 1027-N. Description of "tufa" stone, page 680. 5. "Building Stone News." Building Stone Institute, 420 Lexington Ave., New York 17, New York. An industry newspaper published monthly. 6 Burchard, E. F. "Stone Industry, Arizona." U. S. Geol. Surv. Mineral Re-sources, Part II, page 1345. 1913. An excellent summary for 1913; indicates the potential of Arizona stone, only now being realized. 7. Currier, L. W. "Geologic Appraisal Of Dimension-Stone Deposits." U. S. Geol. Surv. Bulletin 1109, 1960. The only guide to geologic prospecting and evaluation of stone deposits; some emphasis on eastern U. S. deposits. 8. Darton, N. H. "A Resume Of Arizona Geology." Ariz. Bur. Mines Bulletin No. 119. 1925. Old but good geologic information on Arizona geology. 9. Ford, W. E. "Danas Textbook Of Mineralogy." 4th edition, John Wiley Sons, Inc. 1947. The standard "Bible" of mineralogy. 10. "Geologic Map of Arizona." Ariz. Bur. Mines. 1924. Best general picture of geology of Arizona as a whole. Out of print, but copies in some libraries and offices. 11. Geologic maps of Arizona, by counties. Ariz Bur. Mines, 1960-61. Revision of geologic map of Arizona (item 10, above;) The best general guide to prospecting, but may need geologic interpretation; prices of individual county maps, and other information available from Arizona Bureau of Mines, University of Arizona, Tucson, Arizona. 12. Gilluly, James. "General Geology Of Central Cochise County, Arizona." U. S. Geol. Surv. Professional Paper 281, 1956. Excellent geologic description of important formations. 13. "Glossary of Geology and Related Sciences." American Geological Institute, 1957. Accepted standard. 14. "Industrial Minerals and Rocks." Seeley Mudd Series, American Institute Of Mining and Metallurgical Engineers. New York, 1949. Separate chapters on crushed stone, dimension stone, and slate. General geologic, processing and market data. Good bibliographies.,

48 15. Ladoo and Meyers. "Nonmetallic Minerals." MGraw-Hill Book Co., Inc., 1951. General data on production (tables,) and on processing and marketing. 16. "Mineral Resources, Navajo-Hopi Indian Reservations, Arizona-Utah." George A. Kiersch, Director, Univ. of Ariz. Press, 1955. Chapter on dimension stone, pages 60-74, vol. III, is an excellent summary by H. Wesley Peirce. 17. "Pit and Quarry." Pit and Quarry Publications, 431 South Dearborn St., Chicago 5, Illinois. A monthly trade journal promoting use of stone, and including technical data. 18. Rice, C. M. "Dictionary of Geological Terms." Edwards Bros., Inc., Ann Arbor, Michigan, 1948. Accepted standard. 19. "Rock Products." Maclean-Hunter Publishing Corp., 79 West Monroe St., Chicago, Illinois. A monthly trade journal promoting use of stone, and includign technical data. 20. Schrader, F. C. "Mineral Deposits of the Cerbat Range, Black Mountains, and Grand Wash Cliffs, Mohave County, Arizona." U. S. Geol. Surv. Bulletin 397, 1909. Early reports of some deposits. 21. "Stone." Stone Publishing Co., Inc., P. O. Box 846, New Rochelle, New York. A monthly trade journal promoting use of stone, and including technical data. 22. "Stone Work." U. S. General Services Administration, Public Buildings Service, 1955. 13 page pamphlet of stock specifications for stone work, for use by architects and engineers in design of Federal buildings. 23. Tuck, Frank J. "History of Mining In Arizona." Arizona Department of Mineral Resources, 1955. Brief summary on stone, page 38, and production, page 40. 24. U. S. Bureau of Mines Staff. "Mineral Facts And Problems." 1960 Edition, chapter on "Stone" by Wallace W. Key, pages 793-813. Has general bibliography. Treats dimension stone, slate, and crushed or broken stone. General data on specifications, technology, uses, national sta- tistics. 25. U. S. Bureau of Mines Staff. "Minerals Yearbook." Volume 1, Metals and Minerals, U. S. Bur. Mines, 1958. Chapter on "Stone" by Wallace W. Key and Nan C. Jensen, pages 967-1001. Contains national and some state statistics on production and value, partly by types of material and uses; general industrial data; includes brief world review. 26. Wilson, Eldrid D. and Roseveare, George H. "Arizona Nonmetallics." Ariz. Bur. Mines Bulletin 155, 1949. Brief summary of stone activity in Arizona immediately after World War II

49 XII AGENCIES CONCERNED WITH STONE

1. Arizona Department of Mineral Resources, Phoenix, Arizona. Information on stone quarries, stone prospects, production, producers, and operators. 2. Arizona Bureau of Mines, University of Arizona, Tucson, Arizona. Information on stone quarries, stone prospects, geology of Arizona, stone processing. 3. Arizona Development Board, Phoenix, Arizona. Information and aid in industry development. 4. Arizona State Land Department, Phoenix, Arizona. Leases state land for mining and quarrying, information on land status.

5. Employment Security Commission of Arizona, Phoenix, Arizona. Aid in labor placement; information on unemployment compensation. 6. U. S. Geological Survey, Phoenix and Tucson, Arizona. Information on geology of Arizona and on water supplies.

7. U. S. Bureau of Land Management, Phoenix, Arizona. Information on mining and quarrying rights on federal lands, and infor- mation on land status.

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